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Sample records for argentine rangelands recovering

  1. Deforestation of "degraded" rangelands: The Argentine Chaco enters the next stage of the Anthropocene

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twenty years ago I completed my Master’s work in the Chaco forests of northern Argentina. The native forests are, in fact, rangelands. In addition to livestock grazing, there is timber extraction, wildlife harvest (think tegu lizard cowboy boots), and charcoal production. I took part in a project co...

  2. Rangeland Research Roundup -1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Welcome to the inaugural edition of “Rangeland Research Roundup”. Please allow me to introduce myself and provide an overview of our rangeland research in this edition. My name is Justin Derner and I have been the Research Leader for the USDA-Agricultural Research Service (ARS), Rangeland Resources...

  3. RANGELAND SEQUESTRATION POTENTIAL ASSESSMENT

    SciTech Connect

    Lee Spangler; George F. Vance; Gerald E. Schuman; Justin D. Derner

    2012-03-31

    Rangelands occupy approximately half of the world's land area and store greater than 10% of the terrestrial biomass carbon and up to 30% of the global soil organic carbon. Although soil carbon sequestration rates are generally low on rangelands in comparison to croplands, increases in terrestrial carbon in rangelands resulting from management can account for significant carbon sequestration given the magnitude of this land resource. Despite the significance rangelands can play in carbon sequestration, our understanding remains limited. Researchers conducted a literature review to identify sustainably management practices that conserve existing rangeland carbon pools, as well as increase or restore carbon sequestration potentials for this type of ecosystem. The research team also reviewed the impact of grazing management on rangeland carbon dynamics, which are not well understood due to heterogeneity in grassland types. The literature review on the impact of grazing showed a wide variation of results, ranging from positive to negative to no response. On further review, the intensity of grazing appears to be a major factor in controlling rangeland soil organic carbon dynamics. In 2003, researchers conducted field sampling to assess the effect of several drought years during the period 1993-2002. Results suggested that drought can significantly impact rangeland soil organic carbon (SOC) levels, and therefore, carbon sequestration. Resampling was conducted in 2006; results again suggested that climatic conditions may have overridden management effects on SOC due to the ecological lag of the severe drought of 2002. Analysis of grazing practices during this research effort suggested that there are beneficial effects of light grazing compared to heavy grazing and non-grazing with respect to increased SOC and nitrogen contents. In general, carbon storage in rangelands also increases with increased precipitation, although researchers identified threshold levels of

  4. Lawson Aerator applications on rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland drills, brush hogs, Dixie harrows, tandem discs and other equipment have played an important role in treating degraded rangeland environments. The Lawson Aerator is one of the newer implements to enter the scene for rangeland improvements. The Lawson Aerator was designed as a pasture renov...

  5. Is rangeland agriculture sustainable?

    PubMed

    Heitschmidt, R K; Vermeire, L T; Grings, E E

    2004-01-01

    The objective of this paper is to examine the sustainability of rangeland agriculture (i.e., managed grazing) on a world-wide basis, with a focus on North America. Sustainability is addressed on three fronts: 1) ecological, 2) economic, and 3) social acceptance. Based on previous and on-going research, we suggest that employment of science-based rangeland grazing management strategies and tactics can ensure ecological sustainability. The formidable challenge in employing such technology centers around the need to balance efficiency of solar energy capture and subsequent harvest efficiencies across an array of highly spatially and temporally variable vegetation growing conditions using animals that graze selectively. Failure to meet this fundamental challenge often accelerates rangeland desertification processes, and in some instances, enhances rate and extent of the invasion of noxious weeds. We also suggest that the fundamental reason that ecologically sound grazing management technologies are often not employed in the management of grazed ecological systems is because social values drive management decisions more so than ecological science issues. This is true in both well-developed societies with substantial economic resources and in less-developed societies with few economic resources. However, the social issues driving management are often entirely different, ranging from multiple-use issues in developed countries to human day-to-day survival issues in poorly developed countries. We conclude that the long-term sustainability of rangeland agriculture in 1) developed societies depends on the ability of rangeland agriculturalists to continually respond in a dynamic, positive, proactive manner to ever-changing social values and 2) less-developed societies on their ability to address the ecological and social consequences arising from unsustainable human populations before the adoption of science-based sustainable rangeland management technologies.

  6. Drought and rangelands.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Droughts are common and occur regularly in Oklahoma. They’re the most costly natural hazard to the United States, and estimates show a $6-$8 billion annual loss to the nation’s farmers and rancher. With the current drought impacting Oklahoma, people managing rangelands are concerned with the short...

  7. Argentine hemorrhagic fever vaccines.

    PubMed

    Ambrosio, Ana; Saavedra, Maria; Mariani, Mauricio; Gamboa, Graciela; Maiza, Andrea

    2011-06-01

    Argentine hemorrhagic fever (AHF), an acute disease caused by Junin virus (JUNV, Arenaviridae), has been an important issue to public health in Argentina since the early 1950s. The field rodent Calomys musculinus is JUNV natural reservoir and human disease is a consequence of contact with infected rodents. A steady extention of AHF endemic area is being observed since the first reports of the disease. Important achievements have been made in: (a) improvement of methods for the etiological diagnosis; (b) implementation and validation of therapeutical measures; (c) development of vaccines to protect against AHF. Reference is made to different research strategies used to obtain anti-AHF vaccines in the past and anti-arenaviral diseases in the present. Information is updated on features and field performance of Candid #1 vaccine, a live attenuted vaccine currently used to prevent AHF. This vaccine was developed through a joint international effort that envisioned it as an orphan drug. With transferred technology, Argentine government was committed to be Candid #1 manufacturer and to register this vaccine as a novel medical product under the Argentine regulatory authority. Candid #1 vaccine is the first one used to control an arenaviral hemorrhagic fever, the first live viral vaccine to be manufactured and registered in Argentina, reaching its target population through governmental effort.

  8. [Immigration policies in Argentine law].

    PubMed

    Vichich, N P

    1988-12-01

    This paper analyzes contents of Argentine immigration laws in different periods of Argentine history and refers those contents to the State which enforced the corresponding immigration policies and to the socioeconomic structure they support. The Argentine constitution (1852) and subsequent immigration laws define 2 principal guidelines in population and immigration policies: 1) from 1852 until 1955 immigrants are seen as a part of socioeconomic growth, and 2) after 1955 the theory of national security prevails over considerations of an economic nature. With the return to democracy it should be possible to redefine immigration policies considering the country's demographic requirements and the migrants' own needs.

  9. Argentine tango in Parkinson disease.

    PubMed

    2016-10-28

    This article reports on a meta-analysis of 13 studies of the effects of Argentine tango (AT) as a music-based movement therapy for people with Parkinson's disease (PD). Nine studies involved randomised controlled trials.

  10. Mapping rangelands with unmanned aircraft

    Technology Transfer Automated Retrieval System (TEKTRAN)

    At the Jornada Experimental Range in southern New Mexico, ongoing research is aimed at determining the utility of UAS for rangeland mapping and monitoring and developing an operational UAS-based remote sensing program for ecological applications. ...

  11. Whither the Rangeland?: Protection and Conversion in California's Rangeland Ecosystems

    PubMed Central

    Cameron, D. Richard; Marty, Jaymee; Holland, Robert F.

    2014-01-01

    Land use change in rangeland ecosystems is pervasive throughout the western United States with widespread ecological, social and economic implications. In California, rangeland habitats have high biodiversity value, provide significant habitat connectivity and form the foundation for a number of ecosystem services. To comprehensively assess the conservation status of these habitats, we analyzed the extent and drivers of habitat loss and the degree of protection against future loss across a 13.5 M ha study area in California. We analyzed rangeland conversion between 1984 and 2008 using time series GIS data and classified resulting land uses with aerial imagery. In total, over 195,000 hectares of rangeland habitats were converted during this period. The majority of conversions were to residential and associated commercial development (49% of the area converted), but agricultural intensification was surprisingly extensive and diverse (40% across six categories). Voluntary enrollment in an agricultural tax incentive program provided widespread protection from residential and commercial conversions across 37% of the remaining rangeland habitat extent (7.5 M ha), though this program did not protect rangeland from conversion to more intensive agricultural uses. Additionally, 24% of the remaining rangeland was protected by private conservation organizations or public agencies through land or easement ownership while 38% had no protection status at all. By developing a spatial method to analyze the drivers of loss and patterns of protection, this study demonstrates a novel approach to prioritize conservation strategies and implementation locations to avert habitat conversion. We propose that this approach can be used in other ecosystem types, and can serve as a regional conservation baseline assessment to focus strategies to effect widespread, cost-effective conservation solutions. PMID:25141171

  12. Rangeland monitoring with unmanned aerial vehicles (UAVs)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned aerial vehicles (UAVs) have great potential for rangeland management applications, such as monitoring vegetation change, developing grazing strategies, determining rangeland health, and assessing remediation treatment effectiveness. UAVs have several advantages: they can be deployed quickly...

  13. Modeling overland erosion on disturbed rangeland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Rangeland Hydrology and Erosion Model (RHEM) is a new process-based model developed by the USDA-ARS primarily for undisturbed rangeland. Greater sediment detachment rates are usually generated by concentrated flow rather than by sheet flow. Disturbance on rangeland such as fire and tree encroach...

  14. Natural restoration of degraded rangeland ecosystem in Heshan hilly land

    USGS Publications Warehouse

    Hai, R.; Weibing, D.; Jun, W.; Zuoyue, Y.; Qinfeng, G.

    2007-01-01

    This study examined the 20-yr trend of natural restoration of a degraded rangeland ecosystem after disturbance in Heshan hilly land. The results showed that herbs and shrubs were the dominant plants in the community and only a small number of the shade-intolerant tree species had invaded, showing the characteristics of assembly of pioneer communities. The organic matter content, soluble nitrogen, available phosphorus and available potassium had recovered to the level of the local climax community. Part of the ecological functions such as water and soil conservation had also recovered. While the functions of water and soil conservation recovered first, more time was needed for productivity and other functions to completely recover, suggesting the idiosyncratic nature of different ecosystem variables in response to time and microclimate change. Particularly, nutrient cycling recovered very slowly by natural restoration and artificial plantation may be necessary to accelerate the restoration process. ?? 2007 Ecological Society of China.

  15. Contemporary Argentine Cinema during Neoliberalism

    ERIC Educational Resources Information Center

    Rocha, Carolina

    2009-01-01

    In this article I analyze contemporary Argentine cinematic production assessing the impact of Law 24,377 that was implemented in 1995 and that provided much-needed funds for national productions. By looking at film production and consumption, the emergence of young filmmakers and the performance of both commercial films and those belonging to the…

  16. Rangelands: a closing carbon sink?

    NASA Astrophysics Data System (ADS)

    Kuhn, Nikolaus J.

    2016-04-01

    Two thirds of the world's agricultural land is suitable for grazing only. Much of this land has experienced severe erosion due to mismanagement, massive redistribution of soil and sediment, and significant degradation of vegetation. As a consequence, geochemical cycles have changed. Unlike croplands, the impact of degradation on nutrient fluxes is hardly compensated on rangelands, potentially disturbing the carbon cycle because of the declining biomass production and the subsequent conversion of litter into soil organic matter. Over time, the degradation leads to a decline in soil C stocks and, if associated with soil erosion, also to a decline in carbon transfer from soil into sediment sinks. A priory reasoning suggests that during the degradation process, with soil productivity not yet massively affected, the Carbon transfer initially increases because soil erosion rates are also greater than in the non-disturbed system. With most soil degradation in rangelands occurring during the past 200 years, this mechanism on a large part of the global land area could have generated an unintentional terrestrial carbon sink during a time period with increasing industrial CO2 emissions. Using global data on soil degradation, soil erosion, soil carbon stocks and dynamics to simulate their interaction and potential role for rangeland carbon cycles supports the assumption that rangelands may have functioned as a carbon sink, but reveals major uncertainties with regards to the size. This highlights the need to improve our knowledge and understanding of rangeland erosion, landscape change and soil formation, both with regards to the recent past, but also the impacts of their future use and climate.

  17. LOCALIZING THE RANGELAND HEALTH METHOD FOR SOUTHEASTERN ARIZONA

    EPA Science Inventory

    The interagency manual Interpreting Indicators of Rangeland Health, Version 4 (Technical Reference 1734-6) provides a method for making rangeland health assessments. The manual recommends that the rangeland health assessment approach be adapted to local conditions. This technica...

  18. Developing the 18th indicator for interpreting indicators of rangeland health on Northern Great Plains rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    National Resources Inventory (NRI) resource assessment report shows little to no departure on Rangeland Health for most Northern Great Plains Rangelands. This information is supported by Interpreting Indicators of Rangeland Health (IIRH) data collected at local to regional scales. There is however a...

  19. Rangeland research: strategies for providing sustainability and stewardship to the rangelands of the world

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland research is an important determinant of how rangelands are and will be used. Although larger external forces such as national and global economies and social and political attitudes have direct impact on uses of rangelands, the methods by which we implement and evaluate those economic and...

  20. Selection of the Argentine indicator region

    NASA Technical Reports Server (NTRS)

    Ramirez, C. J.; Reed, C. R. (Principal Investigator)

    1982-01-01

    Determined from available Argentine crop statistics, selection of the Indicator Region was based on the highest wheat, corn, and soybean producing provinces, which were: Buenos Aires, Cordoba, Entre Rios, and Santa Fe. Each province in Argentina was examined for the availability of LANDSAT data; area, yield and production statistics; crop calendars; and other ancillary data. The Argentine Indicator Region is described.

  1. Trap-mulching Argentine ants.

    PubMed

    Silverman, Jules; Sorenson, Clyde E; Waldvogel, Michael G

    2006-10-01

    Argentine ant, Linepithema humile (Mayr), management is constrained, in large part, by polydomy where nestmates are distributed extensively across urban landscapes, particularly within mulch. Management with trap-mulching is a novel approach derived from trap-cropping where ants are repelled from a broad domain of nest sites to smaller defined areas, which are subsequently treated with insecticide. This concept was field-tested with mulch surrounding ornamental trees replaced with a narrow band of pine (Pinus spp.) needle mulch (trap) within a much larger patch of repellent aromatic cedar (Juniperus spp.) mulch. After ants reestablished around the trees, the pine needle mulch band was treated with 0.06% fipronil (Termidor). Poor results were obtained when the trap extended from the tree trunk to the edge of the mulched area. When the trap was applied as a circular band around the tree trunk reductions in the number of foraging ants were recorded through 14 d compared with an untreated mulch control, but not for longer periods. Reductions in the number of ant nests within mulch were no different between the trap mulch and any of the other treatments. We conclude that trap-mulching offers limited benefits, and that successful management of Argentine ants will require implementation of complementary or perhaps alternative strategies.

  2. CARBON FLUXES ON NORTH AMERICAN RANGELANDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seasonal patterns of growth and thus carbon uptake are relevant to both scientists who study ecosystem properties and managers who strive to maintain rangeland productivity. We studied seasonal patterns of net ecosystem exchange of carbon (NEE) on 11 US rangelands over a 6-year period. All sites w...

  3. Monitoring Rangeland Health by Remote Sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Based on a land-cover classification from NASA’s MODerate resolution Imaging Spectroradiometer (MODIS), rangelands cover 48% of the Earth’s land surface, not including Antarctica. Nearly all analyses imply the most economical means of monitoring large areas of rangelands worldwide is with remote s...

  4. Multiple Scale Remote Sensing for Monitoring Rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Based on a land-cover classification from NASA’s MODerate resolution Imaging Spectroradiometer (MODIS), rangelands cover 48% of the Earth’s land surface, not including Antarctica. Nearly all analyses imply the most economical means of monitoring large areas of rangelands worldwide is with remote se...

  5. Monitoring response to disturbance in dynamic rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Arid and semi-arid rangelands worldwide provide important ecosystem services and see a diversity of land uses. To maintain the health of these lands, it is necessary to monitor rangeland conditions in response to management and disturbance. Spatial patterns from disturbance are superimposed on patte...

  6. Rangeland sequestration potential assessment (Final Report)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangelands occupy approximately half of the world's land area and store greater than 10% of the terrestrial biomass carbon and up to 30% of the global soil organic carbon. Although soil carbon sequestration rates are generally low on rangelands in comparison to croplands, increases in terriestrial c...

  7. Applying animal behavior to arid rangeland mangement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Livestock production is one of many demands placed on today’s arid rangelands. Therefore, understanding plant and animal biology and their effects on biotic and abiotic landscape components is fundamental if rangelands are to remain ecologically sustainable. One limiting factor to accomplishing posi...

  8. Valuation of rangeland ecosystem services

    USGS Publications Warehouse

    Gascoigne, W.R.

    2011-01-01

    Economic valuation lends itself well to the anthropocentric orientation of ecosystem services. An economic perspective on ecosystems portrays them as natural assets providing a flow of goods and services valuable to individuals and society collectively. A few examples include the purification of drinking water, reduced risk from flooding and other extreme events, pollination of agricultural crops, climate regulation, and recreation opportunities from plant and animal habitat maintenance, among many others. Once these goods and services are identified and quantified, they can be monetized to complete the valuation process. The monetization of ecosystem goods and services (in the form of dollars) provides a common metric that allows for cross-comparison of attributes and evaluation of differing ecological scenarios. Complicating the monetization process is the fact that most of these goods and services are public and non-market in nature; meaning they are non-rival and non-exclusive and are typically not sold in a traditional market setting where monetary values are revealed. Instead, one must employ non-market valuation techniques, with primary valuation methods typically being very time and resource consuming, intimidating to non-economists, and often impractical. For these reasons, benefit transfer methods have gained popularity. This methodology harnesses the primary collection results of existing studies to make inferences about the economic values of non-market goods and services at an alternative policy site (in place and/or in time). For instance, if a primary valuation study on oak reestablishment on rangelands in southern California yielded a value of $30 per-acre associated with water regulation, this result can be transferred, with some adjustments, to say something about the value of an acre of oaks on rangelands in northern portions of the state. The economic valuation of rangeland ecosystem services has many roles. Economic values may be used as input

  9. Meadow degradation, hydrological processes and rangeland management in Tibet

    NASA Astrophysics Data System (ADS)

    He, Siyuan; Richards, Keith

    2013-04-01

    Alpine meadow dominated by species of Kobresia is widely distributed in the Tibetan Plateau. Kobresia pygmaea is often a main species and the meadow has evolved as a result of long-term trampling, being a main rangeland resource for livestock grazing. This alpine meadow also plays an important role in regulating the water and energy balance through land-atmosphere interaction, leaving an impact on local hydrological processes and beyond. Therefore, alpine meadow degradation is detrimental to both the health of the ecosystems, and to pastoralism. This research therefore studies the hydrological process with regard to degradation of Kobresia pygmaea meadow, tracing the possible causes, detecting the impacts on soil and biological properties, and further considering the herders' role in future rangeland management. The study area is around the Kema village of the Nagqu Prefecture in Northern Tibet, where human population depends on livestock grazing for livelihood. Main driving factors of alpine meadow degradation are climatic variations and human disturbance. The periodical change in local climate may be related to quasi-oscillatory atmospheric circulations in this monsoon dominated area and the climatic trends with extreme weather conditions can make the whole system hard to recover. Along with climatic variations, overgrazing is predominant with an exceeding of the carrying capacity by almost every household in this village. This is related to the change of rangeland management by the policies of privatisation of pasture and sedentarisation. The acceleration of degradation since the 1980s results in a series of distinct soil-vegetation combination classified in this research as the normal meadow, compact crust and bare soil. The species composition, soil physical and chemical properties and the vertical water movement along the soil-plant-atmosphere continuum are significantly different at the sites representing stages of degradation, revealed by multiple methods

  10. Revegetating sagebrush rangelands invaded by medusahead

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to determine: 1) effective treatments for controlling medusahead and 2) the appropriate plant materials for revegetating medusahead-invaded rangelands. Initial treatments of prescribed burning immediately followed with applications of the preemergent herbicide imaza...

  11. Revegetating sagebrush rangelands invaded by medusahead

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study are to determine: 1) effective treatments for controlling medusahead and 2) the appropriate plant materials for revegetating medusahead-invaded rangelands. Initial treatments of prescribed burning immediately followed with applications of the preemergent herbicide imazap...

  12. Rehabilitation of degraded rangelands: lessons learned

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The introduction and subsequent invasion of cheatgrass (Bromus tectorum) has had astronomical effects to Great Basin rangelands. Cheatgrass has truncated secondary succession by outcompeting native plant species for limited resources, thus building persistent seed banks that take advantage of condi...

  13. Climate change mitigation and adaptation in rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland ecosystems are multifaceted biophysical systems with highly variable soils, weather, landforms, animals, and vegetation that are manifest in complex management options which involve diverse human goals, values, beliefs and decision-making strategies. Overlaying this vast background variabi...

  14. Aerospace video imaging systems for rangeland management

    NASA Technical Reports Server (NTRS)

    Everitt, J. H.; Escobar, D. E.; Richardson, A. J.; Lulla, K.

    1990-01-01

    This paper presents an overview on the application of airborne video imagery (VI) for assessment of rangeland resources. Multispectral black-and-white video with visible/NIR sensitivity; color-IR, normal color, and black-and-white MIR; and thermal IR video have been used to detect or distinguish among many rangeland and other natural resource variables such as heavy grazing, drought-stressed grass, phytomass levels, burned areas, soil salinity, plant communities and species, and gopher and ant mounds. The digitization and computer processing of VI have also been demonstrated. VI does not have the detailed resolution of film, but these results have shown that it has considerable potential as an applied remote sensing tool for rangeland management. In the future, spaceborne VI may provide additional data for monitoring and management of rangelands.

  15. Treatment of Argentine hemorrhagic fever.

    PubMed

    Enria, Delia A; Briggiler, Ana M; Sánchez, Zaida

    2008-04-01

    Argentine hemorrhagic fever (AHF) is a rodent-borne illness caused by the arenavirus Junin that is endemic to the humid pampas of Argentina. AHF has had significant morbidity since its emergence in the 1950s, with a case-fatality rate of the illness without treatment between 15% and 30%. The use of a live attenuated vaccine has markedly reduced the incidence of AHF. Present specific therapy involves the transfusion of immune plasma in defined doses of neutralizing antibodies during the prodromal phase of illness. However, alternative forms of treatment are called for due to current difficulties in early detection of AHF, related to its decrease in incidence, troubles in maintaining adequate stocks of immune plasma, and the absence of effective therapies for severely ill patients that progress to a neurologic-hemorrhagic phase. Ribavirin might be a substitute for immune plasma, provided that the supply is guaranteed. Immune immunoglobulin or monoclonal antibodies should also be considered. New therapeutic options such as those being developed for systemic inflammatory syndromes should also be valuated in severe forms of AHF.

  16. Estimating Sediment Yield on Disturbed Rangeland Using the Rangeland Hydrology and Erosion Model (RHEM)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Rangeland Hydrology and Erosion Model (RHEM) is an event-based model that estimates runoff, erosion, and sediment delivery rates and volumes at the spatial scale of the hillslope and the temporal scale of a single rainfall event. It represents erosion processes on normal rangeland, as well as, r...

  17. USDA internet tool to estimate runoff and soil loss on rangelands: rangelands hydrology and erosion model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangelands are the most dominant land cover type in the United States (770 million acres) with approximately 53% of the nation’s rangelands owned and managed by the private sector, while approximately 43% are managed by the federal government. Information on the type, extent, and spatial location of...

  18. Using rangeland health assessment to inform successional management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland health assessment provides qualitative information on ecosystem attributes. Successional management is a conceptual framework that allows managers to link information gathered in rangeland health assessment to ecological processes that need to be repaired to allow vegetation to change in ...

  19. Antiviral treatment of Argentine hemorrhagic fever.

    PubMed

    Enria, D A; Maiztegui, J I

    1994-01-01

    Argentine hemorrhagic fever is a systemic viral disease caused by Junin virus, with a mortality of 15-30% in untreated individuals. Current specific therapy is highly effective in reducing mortality, and consists of the early administration of immune plasma in defined doses of specific neutralizing antibodies per kg of body weight. However, several reasons suggest the need to investigate alternative therapies. Ribavirin, a broad spectrum antiviral agent, is effective in the treatment of other viral hemorrhagic fevers, and the studies done with Junin virus infections to date indicate that this drug may also have a beneficial effect in Argentine hemorrhagic fever.

  20. Terpenoids and bibenzyls from three Argentine liverworts.

    PubMed

    Nagashima, Fumihiro; Asakawa, Yoshinori

    2011-12-16

    A new rosane diterpenoid, 3a-hydroxy-5,15-rosadien-11-one (3), was isolated, together with a known rosane diterpenoid, 5,15-rosadiene-3,11-dione (4), and an aromadendrane sesquiterpenoid, ent-cyclocolorenone (5), from the Et(2)O extract of an unidentified Argentine liverwort Anastrophyllum species. Moreover, four known sesquiterpene lactones 6-9 and two known bibenzyls 10, 11 were isolated from the Et(2)O extracts of Argentine Frullania brasiliensis and Radula voluta, respectively. The structures of compounds 3-11 were determined by the use of NMR techniques.

  1. Identifying rangeland restoration targets: an appraisal of challenges and opportunities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A common challenge to initiating restoration on rangelands is identifying realistic restoration targets. This challenge must be confronted if ecological restoration and rangeland management are to be fully integrated so that timely interventions can assist the recovery of degraded rangelands. To a...

  2. 75 FR 8036 - Monitor-Hot Creek Rangeland Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-23

    ... Forest Service Monitor-Hot Creek Rangeland Project AGENCY: Forest Service, USDA. ACTION: Notice of intent... continued livestock grazing ] within the Monitor-Hot Creek Rangeland Project area. The analysis will... conditions within the Monitor-Hot Creek Rangeland Project area towards desired conditions. The project...

  3. 43 CFR 4180.1 - Fundamentals of rangeland health.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Fundamentals of rangeland health. 4180.1... Fundamentals of Rangeland Health and Standards and Guidelines for Grazing Administration § 4180.1 Fundamentals of rangeland health. Standards and guidelines developed or revised by a Bureau of Land...

  4. 43 CFR 4180.1 - Fundamentals of rangeland health.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Fundamentals of rangeland health. 4180.1... Fundamentals of Rangeland Health and Standards and Guidelines for Grazing Administration § 4180.1 Fundamentals of rangeland health. Standards and guidelines developed or revised by a Bureau of Land...

  5. Sediment source determination using fallout Cesium-137 in arid rangelands.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sediment source identification in arid rangelands is necessary to understanding rangeland conditions and developing management practices to improve rangeland health and reduce sediment load to streams. The purpose of this research was to use Cesium-137 to identify sources of sediments in an arid ran...

  6. Western rangelands: overgrazed and undermanaged

    SciTech Connect

    Sheridan, D.

    1981-05-01

    Overgrazing and poor management of the western arid lands causes desertification as the levels of water tables and surface waters drop, top soil and surface waters become more saline, soil erodes, and native vegetation disappears. This process had led to severe desertification in an estimated 1.1 million square miles and very severe desertification on 10,500 square miles in the US. The three areas in the very severe category occur in the Navajo Indian reservation in Arizona and New Mexico and on either side of El Paso, Texas. All were subjected to overgrazing. Government policies have only recently tried to bring public land grazing in line with the land's carrying capacity by focusing on long-term productivity. The Public Rangelands Improvement Act of 1978 authorizes better management and multiple use of public lands, but the Bureau of Land Management has not established an effective monitoring system to ensure its implementation or to overcome political constraints against reducing livestock. Ranchers disagree with the assessments made by scientists and support vegetation modification instead of grazing allotments. 58 references, 7 figures. (DCK)

  7. Radiation Studies with Argentine Ion Exchange Material

    SciTech Connect

    Crawford, C.L.

    2002-06-28

    A recent technology exchange between Argentina Nuclear Energy Commission (CNEA) and the US Department of Energy involved vitrification studies of ion exchange resins. Details of the spent ion exchange resins currently stored at two Argentine nuclear power plants, Atucha I and Embalse, have been presented in earlier reports. The present study examines irradiation of simulant samples of ion exchange resins.

  8. National estimates of soil loss on rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since 1995, an interagency group composed of the Natural Resources Conservation Service, Agricultural Research Service, and U.S. Geological Survey have worked together to develop a robust field approach for National Resource Inventory (NRI) on rangeland. The new NRI protocols are designed to detect ...

  9. Is rangeland health relevant to Mongolia?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Approximately 800,000 of Mongolia’s 2.5 million people depend directly on livestock production and rangelands for their livelihood. Overgrazing is widespread in the western provinces and near the capital city of Ulaanbaatar, while forage is often underutilized in eastern parts of the country. The ra...

  10. Rehabilitation of cheatgrass-infested rangelands: concepts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The introduction and subsequent invasion of cheatgrass (Bromus tectorum) onto millions of acres of Intermountain West rangelands has caused astronomical changes to numerous ecosystems and the multiple uses that depend on healthy and functional ecosystems. This is the first part, of a 3-part series ...

  11. Rehabilitation of cheatgrass-infested rangelands: management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is the final part of a three part series specifically addressing lessons learned concerning the management of rehabilitated cheatgrass-infested rangelands. Steve Novak and Richard Mack reported in 2003 that they found no evidence of outcrossing in 2,000 cheatgrass seedlings from 60 North Americ...

  12. Importance of shrub restoration on rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The recognition of brush species and the browse these plants provide as an important component of rangeland production was often overlooked in land management for some time. Even after the birth of range management in the early twentieth century, herbaceous species were considered the basic componen...

  13. Adaptive management for drought on rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adaptive management for drought on rangelands encompasses 1) enterprise flexibility – herd structure where the proportion of cow-calf pairs and yearlings provides plasticity to match forage availability with forage demand, with advantages to economic returns and increased resiliency of plant communi...

  14. Managing Complex Problems in Rangeland Ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Management of rangelands, and natural resources in general, has become increasingly complex. There is an atmosphere of increasing expectations for conservation efforts associated with a variety of issues from water quality to endangered species. We argue that many current issues are complex by their...

  15. Turning information into knowledge for rangeland management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The kind of knowledge system that will be capable of meeting the needs of rangeland managers will evolve as scientists, technology specialists, managers, and biologists find ways to integrate the ever expanding array of information systems and tools to meet their needs. The tools and techniques high...

  16. 75 FR 53731 - Culturally Significant Objects Imported for Exhibition Determinations: “Contemporary Argentine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ... for Exhibition Determinations: ``Contemporary Argentine Masterworks'' SUMMARY: Notice is hereby given... hereby determine that the objects to be included in the exhibition ``Contemporary Argentine...

  17. SAC-B, Argentine scientific satellite

    NASA Technical Reports Server (NTRS)

    Gulich, J. M.; White, C.

    1994-01-01

    The project and the missions of the Argentine scientific satellite, SAC-B, are summarized. SAC-B is an international cooperative project between NASA and the Secretariat of State of Science and Technology of the Argentine Republic. The objective of SAC-B is to advance the study of solar physics and astrophysics through the examination of solar flares, gamma ray burst sources and the diffuse soft X-ray cosmic background. The scientific payload comprises an instrument to measure the temporal evolution of X-ray emissions from solar flares as well as nonsolar gamma ray bursts, a combined soft X-ray and gamma ray burst detector, a diffuse X-ray background detector, and an energetic neutral atoms detector.

  18. Chlorofluorocarbon distributions in the deep Argentine Basin

    SciTech Connect

    Warner, M.J. ); Weiss, R.F. ); Smethie, W.M. Jr. )

    1990-01-09

    The seawater concentrations of the chlorofluorocarbons (CFCs) F-11 and F-12 were measured in the Argentine Basin during the Abyssal Boundary Current Studies (1986) and the South Atlantic Ventilation Experiment (1988-89) expeditions. In most regions of the basin, the CFC concentrations are above the detection limit (0.015 pmol/kg) in the entire water column. The main features of the F-11 and F-12 profiles in the deep waters of the Argentine Basin are concentration mixima at depths of 2 to 3 km and generally increasing concentrations towards the bottom. The mid-depth CFC minima are associated with the salinity maximum of Circumpolar Deep Water (CDW). The higher CFC concentrations at the seafloor are correlated with the colder temperatures of Antarctic Bottom Water (AABW). The CFC concentrations in AABW are highest on the eastern portion of the basin along 47[degrees]S and along the southern and western boundaries. These distributions are consistent with a separation of the inflowing AABW into a cyclonic gyre in the eastern portion of the basin and a western boundary current which carries a detectable CFC singal as far noth as 17[degrees]S. Between CDW and AABW, there are local CFC maxima and minima which are not associated with extrema in other hydrographic properties. The local minima are found on a mean density of 46.07 [sigma][sub 4], which is the upper bound of the water entering the Argentine Basin from the Weddell Sea (Reid, Deep-Sea Res., 1989 submitted). The local CFC maxima are found at about the 46.00 [sigma][sub 4] isopycnal surface. Water of this density apparently is of circumpolar origin. The presence of these local CFC extrema in this density range carries information on the time-dependent vertical mixing in the deep Argentine Basin.

  19. REVEGETATION SUCCESS OF MEDUSAHEAD-INFESTED RANGELANDS WITH PLATEAU® AND PRESCRIBED BURNING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Medusahead (Taeniatherum caput-medusae (L.) Nevski) is an invasive annual grass that is rapidly invading rangelands. Medusahead invasion reduces the productivity and biodiversity of rangelands. Efforts to control medusahead and revegetation infested rangelands are often unsuccessful. We evaluated...

  20. Sediment Budgets and Source Determination Using Fallout Cesium-137 in Semiarid Rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Analysis of soil redistribution and sediment sources in semiarid and arid rangelands can provide information for understanding watershed sediment budgets and rangeland conditions and for implementing management practices to improve rangeland conditions and reduce sediment loads in streams. The purpo...

  1. Rangeland Rummy - a board game to support adaptive management of rangeland-based livestock systems.

    PubMed

    Farrié, B; Jouven, M; Launay, F; Moreau, J-C; Moulin, C-H; Piquet, M; Taverne, M; Tchakérian, E; Thénard, V; Martin, G

    2015-01-01

    Rangeland-based livestock systems have to deal with the significant instability and uncertainty of the agricultural context (policy changes, volatility of input prices, etc.), and especially of the climatic context. Thus, they are particularly concerned by adaptive management strategies. To support the development of such strategies, we developed a board game including a computer model called "Rangeland Rummy". It is to be used by groups of farmers and agricultural consultants in the context of short workshops (about 3 h). Rangeland Rummy builds upon five types of material object: (i) a game board; (ii) a calendar stick indicating the starting date of the game board; (iii) sticks marked with the feed resources available for combinations of vegetation types and their management practices; (iv) cards to define animal groups and their feeding requirements throughout the year; (v) cards related to types of feed that can be attributed to animal groups throughout the year. Using these material objects, farmers collectively design a rangeland-based livestock system. This system is immediately evaluated using a computer model, i.e. a spreadsheet providing graphs and indicators providing information on, among other things, the extent to which quantitative and qualitative animal feeding requirements are covered across the year. Playing the game thus consists in collectively and iteratively designing and evaluating rangeland-based livestock systems, while confronting the players with new contextual challenges (e.g. interannual variability of weather, volatility of input prices) or new farmers' objectives (e.g. being self-sufficient for animal feeding). An example of application of Rangeland Rummy with 3 farmers in southern France is reported. Applications show that it tends to develop farmers' adaptive capacity by stimulating their discussions and the exchange of locally-relevant knowledge on management strategies and practices in rangeland-based livestock systems.

  2. A qualitative evaluation of Landsat imagery of Australian rangelands

    USGS Publications Warehouse

    Graetz, R.D.; Carneggie, David M.; Hacker, R.; Lendon, C.; Wilcox, D.G.

    1976-01-01

    The capability of multidate, multispectral ERTS-1 imagery of three different rangeland areas within Australia was evaluated for its usefulness in preparing inventories of rangeland types, assessing on a broad scale range condition within these rangeland types, and assessing the response of rangelands to rainfall events over large areas. For the three divergent rangeland test areas, centered on Broken W, Alice Springs and Kalgoorlie, detailed interpretation of the imagery only partially satisfied the information requirements set. It was most useful in the Broken Hill area where fenceline contrasts in range condition were readily visible. At this and the other sites an overstorey of trees made interpretation difficult. Whilst the low resolution characteristics and the lack of stereoscopic coverage hindered interpretation it was felt that this type of imagery with its vast coverage, present low cost and potential for repeated sampling is a useful addition to conventional aerial photography for all rangeland types.

  3. Integration of Hyperspectral Data for Rangeland Characterization

    SciTech Connect

    Petrie, Gregg M.; Cullinan, Valerie I.; Cadwell, Larry L.; Downs, Janelle L.; Perry, Eileen M.; Turner, Jim

    2000-12-30

    Grazing lands in the United States consist of approximately 312 million hectares of federal, state, and private land. A recent review by the National Research Council indicates a need to collect comprehensive, consistent, and uniform data to evaluate rangeland health. The Pacific Northwest National Laboratory (PNNL) is assisting the U.S. Bureau of Land Management, and working cooperatively with the U.S. Forest Service, and the U.S. Natural Resource Conservation Service to address these data needs using new remote sensing methods designed to characterize large areas quickly and at minimal cost. Anticipated application for new remote sensing protocols range from conducting national assessments of the ecological condition of rangelands to monitoring change in condition of individual grazing allotments.

  4. Insecticide Transfer Efficiency and Lethal Load in Argentine Ants

    PubMed Central

    Hooper-Bui, L.M.; Kwok, E.S.C.; Buchholz, B.A.; Rust, M.K.; Eastmond, D.A.; Vogel, J.S.

    2015-01-01

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of 14C-sucrose, 14C-hydramethylnon, and 14C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), but dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). The distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. Bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony. PMID:26504258

  5. Insecticide transfer efficiency and lethal load in Argentine ants

    NASA Astrophysics Data System (ADS)

    Hooper-Bui, L. M.; Kwok, E. S. C.; Buchholz, B. A.; Rust, M. K.; Eastmond, D. A.; Vogel, J. S.

    2015-10-01

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of 14C-sucrose, 14C-hydramethylnon, and 14C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), but dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). The distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. Bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.

  6. Insecticide Transfer Efficiency and Lethal Load in Argentine Ants

    SciTech Connect

    Hooper-Bui, L. M.; Kwok, E S.C.; Buchholz, B. A.; Rust, M. K.; Eastmond, D. A.; Vogel, J. S.

    2015-07-03

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of 14C-sucrose, 14C-hydramethylnon, and 14C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), but dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). Moreover, the distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. The bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.

  7. Insecticide Transfer Efficiency and Lethal Load in Argentine Ants

    DOE PAGES

    Hooper-Bui, L. M.; Kwok, E S.C.; Buchholz, B. A.; ...

    2015-07-03

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of 14C-sucrose, 14C-hydramethylnon, and 14C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), butmore » dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). Moreover, the distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. The bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.« less

  8. Hydrocarbon prospectivity of the Argentine Continental Slope

    SciTech Connect

    Light, M.P.R.; Keeley M.L.; Maslanyj, M.P.; Urien, C.M.; Hoggs, S.L.

    1993-02-01

    A rift basin containing stratigraphic and structural closures is developed along the Argentine slope over a distance of some 1000 km and area of 50,000 km[sup 2] in potentially exploitable water depths of 200 to 1500 m. No wells exist on this part of the continental margin. Rifting began during the Late Triassic/Jurassic and ended in Early Cretaceous. The first marine seaways flooded the Rift alluvial plains and lake. In Hauterian-Barrenian time, low circulation marine conditions with oxygen deficiency prevailed up to Rio Grande/Walvis Ridge flooding in part the coastal pull-apart basins. A major marine transgression in the Maastrichtian formed a widespread seal over the entire shelf and slope area. Four play types were identified: (1) a major north-east trending elongate delta system sourced inland from the San Julien (N. Malvinas) Basin and deposited on the southern Patagonian shelf and rise, (2) reworked deltaic barrier sands accumulated along the crest of the Outer Basement Ridge, (3) The Outer Basement Ridge, a major structural closure 400 km long, and (4) a series of margin-parallel rift systems in the offshore region between the 200 m and 1500 m isobaths. Regional seismic data and geological correlations suggest that oil prone source rocks are likely in the Middle and Upper Jurassic and Cretaceous formations. Source rocks are probably mature east and west of the Outer Basement Ridge and in the easterndepocenter of the Colorado Basin. Eastward migration from Jurassic age lacustrine source rocks in the Colorado Basin may have charged traps along the crest of the Outer Basement Ridge. Westward directed migration from deeply buried Aptian age marine source rocks in the Atlantic basins has probably charged prospective stratigraphic and structural traps in a suite of coast-parallel grabens developed on the Argentine continental shelf and slope. The Argentine offshore region, therefore, offers significant encouragement as a productive hydrocarbon province.

  9. Variation in ecological resilience: a fundamental concept for rangeland ecology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The concepts and terminology associated with ecological resilience are fast becoming a common language for the study of global change. We review the application of the broad concept of resilience to rangeland ecology, connecting it to several well-established rangeland concepts including equilibrial...

  10. Practical and effective rehabilitation of rangelands: lessons learned

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Disturbed rangelands present significant challenges to land managers and private land owners. Controversy exists on the approach as to how to restore or rehabilitate these degraded rangelands. The proper use of plant materials and aggressive weed control practices can significantly increase the succ...

  11. New research themes after a century of rangeland science

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rangeland science profession in the United States has its roots in the widespread overgrazing and concurrent severe droughts of the late 19th Century. These drivers contributed to rangeland resource degradation especially in the American Southwest. Experimental stations like those established ea...

  12. Rehabilitation of cheatgrass-infested rangelands: applications and practices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The challenges that land owners and resource managers face when trying to attempt applications and practices when attempting to rehabilitate rangelands infested with cheatgrass (Bromus tectorum) are over-whelming. Simply purchasing seed and spreading it throughout the rangelands is doomed for failu...

  13. Strategies for sustaining multiple ecosystem services from rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The application of natural resource science to both management needs and policy formation has been spotty, at best. Interestingly, rangeland science had an early history of closely supporting management needs and USA rangeland policies during the early 20th century. This history of support unrave...

  14. The western United States rangelands, a major resource

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland is a type of land found predominantly in arid and semiarid regions, and managed as a natural ecosystem supporting vegetation of grasses, grass-like plants, forbs, or shrubs. There are approximately 761 m ac of rangeland in the United States, about 31% of the total land area. This land ty...

  15. Making spatial predictions of rangeland ecosystem attributes using regression kriging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sound rangeland management requires accurate information on condition over large landscapes. Typical approaches to making spatial predictions rangeland condition attributes (e.g., shrub or bare ground cover) are via regression between field and remotely-sensed data. This works well in some situation...

  16. INTEGRATED MANAGEMENT OF LEAFY SPURGE-INFESTED RANGELAND

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge is an invasive Eurasian weed on pastures and rangeland in North America where it reduces grass forage production. Our objective was to determine the effects of multispecies grazing combined with Aphthona 'ea beetles on leafy spurge-infested rangeland. On two western North Dakota sites d...

  17. Conservation program participation and adaptive rangeland decision-making

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper analyzes rancher participation in conservation programs in the context of a social-ecological framework for adaptive rangeland management. We argue that conservation programs are best understood as one of many strategies of adaptively managing rangelands in ways that sustain livelihoods a...

  18. Spatial redistribution of nitrogen by cattle in semiarid rangeland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nitrogen (N) availability can strongly influence forage quality and the capacity for semiarid rangelands to respond to increasing atmospheric CO2. Although many pathways of nitrogen input and loss from rangelands have been carefully quantified, cattle-mediated N losses are often poorly understood. W...

  19. Weather variability and adaptive management for rangeland restoration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inherent weather variability in upland rangeland systems requires relatively long-term goal setting, and contingency planning for partial success or failure in any given year. Rangeland plant communities are dynamic systems and successional planning is essential for achieving and maintaining system...

  20. Sustaining working rangelands: Insights from rancher decision making

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grazed rangeland ecosystems encompass diverse global land resources, and are complex social-ecological systems from which society demands both goods (e.g., livestock and forage production) and services (e.g., abundant and high quality water). In the dialogue on rangeland conservation and sustainable...

  1. Grand challenges for resilience-based management of rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The social and ecological contexts for rangeland management are changing rapidly, prompting a reevaluation of science, management, and the linkages between them. Here, we argue that the recent transformation from a steady state to an ecosystem management model has served the rangeland profession wel...

  2. Developing an operational rangeland water requirement satisfaction index

    USGS Publications Warehouse

    Senay, Gabriel B.; Verdin, James P.; Rowland, James

    2011-01-01

    Developing an operational water requirement satisfaction index (WRSI) for rangeland monitoring is an important goal of the famine early warning systems network. An operational WRSI has been developed for crop monitoring, but until recently a comparable WRSI for rangeland was not successful because of the extremely poor performance of the index when based on published crop coefficients (K c) for rangelands. To improve the rangeland WRSI, we developed a simple calibration technique that adjusts the K c values for rangeland monitoring using long-term rainfall distribution and reference evapotranspiration data. The premise for adjusting the K c values is based on the assumption that a viable rangeland should exhibit above-average WRSI (values >80%) during a normal year. The normal year was represented by a median dekadal rainfall distribution (satellite rainfall estimate from 1996 to 2006). Similarly, a long-term average for potential evapotranspiration was used as input to the famine early warning systems network WRSI model in combination with soil-water-holding capacity data. A dekadal rangeland WRSI has been operational for east and west Africa since 2005. User feedback has been encouraging, especially with regard to the end-of-season WRSI anomaly products that compare the index's performance to ‘normal’ years. Currently, rangeland WRSI products are generated on a dekadal basis and posted for free distribution on the US Geological Survey early warning website at http://earlywarning.usgs.gov/adds/

  3. Rangeland Hydrology and Erosion Model (RHEM) enhancements for applications on disturbed rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Rangeland Hydrology and Erosion Model (RHEM) is a new process-based model developed by the USDA-ARS. Disturbance such as fire or woody plant encroachment can amplify overland flow erosion by increasing the likelihood of concentrated flow formation. In this study, we enhanced RHEM applications on...

  4. Modeling soil erosion impact of rangeland disturbance using the Rangeland Hydrology and Erosion Model (RHEM)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Disturbance on rangeland such as fire and tree encroachment can increase overland flow erosion rate by increasing the likelihood of concentrated flow formation on a more erodible surface. In this study, we made advancements to RHEM by developing a new version of the model to predict concentrated flo...

  5. The widespread collapse of an invasive species: Argentine ants (Linepithema humile) in New Zealand.

    PubMed

    Cooling, Meghan; Hartley, Stephen; Sim, Dalice A; Lester, Philip J

    2012-06-23

    Synergies between invasive species and climate change are widely considered to be a major biodiversity threat. However, invasive species are also hypothesized to be susceptible to population collapse, as we demonstrate for a globally important invasive species in New Zealand. We observed Argentine ant populations to have collapsed in 40 per cent of surveyed sites. Populations had a mean survival time of 14.1 years (95% CI = 12.9-15.3 years). Resident ant communities had recovered or partly recovered after their collapse. Our models suggest that climate change will delay colony collapse, as increasing temperature and decreasing rainfall significantly increased their longevity, but only by a few years. Economic and environmental costs of invasive species may be small if populations collapse on their own accord.

  6. Grazing behavioral responses of beef cattle to medusahead invasion in sagebrush steppe rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study are to determine: 1) seasonal forage quality of medusahead-invaded rangeland relative to adjacent rangeland supporting desirable vegetation; 2) relative grazing preference of beef cattle for medusahead-invaded rangeland and adjacent rangeland supporting desirable vegetat...

  7. Sustainable rangeland management, economic growth, and a cautious role for the SRM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest in the art and science of rangeland management increased dramatically during the 20th century and it was out of this interest that the profession of rangeland management was born. As public interest in rangeland management grew, so did the number, breadth, and depth of rangeland management ...

  8. Rangeland health assessment - The key to understanding and assessing rangeland soil health in the Northern Great Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As the science related to soil and rangeland health evolves, so do their protocols and assessment methodologies. Rangeland health assessments consist of evaluating how well ecological processes such as the water cycle, energy flow and nutrient cycling are functioning at a site. Soil health is the ca...

  9. Maintaining ecosystem services through continued livestock production on California rangelands

    NASA Astrophysics Data System (ADS)

    Barry, S.; Becchetti, T.

    2015-12-01

    Nearly 40% of California is rangeland comprising the largest land type in California and providing forage for livestock, primarily beef cattle. In addition to forage, rangelands provide a host of ecosystem systems services, including habitat for common and endangered species, fire fuels management, pollination services, clean water, viewsheds, and carbon sequestration. Published research has documented that most of these ecosystem services are positively impacted by managed livestock grazing and rancher stewardship. Ranchers typically do not receive any monetary reimbursement for their stewardship in providing these ecosystem services to the public. Markets have been difficult to establish with limited ability to adequately monitor and measure services provided. At the same time, rangelands have been experiencing rapid conversion to urbanization and more profitable and intensive forms of agriculture such as almond and walnut orchards. To prevent further conversion of rangelands and the loss of the services they provide, there needs to be a mechanism to identify and compensate landowners for the value of all products and services being received from rangelands. This paper considers two methods (opportunity cost and avoided cost) to determine the value of Payment for Ecosystem Services (PES) for rangelands. PES can raise the value of rangelands, making them more competitive financially. Real estate values and University of California Cooperative Extension Cost Studies, were used to demonstrate the difference in value (lost opportunity cost) between the primary products of rangelands (livestock production) and the products of the converted rangelands (almond and walnut orchards). Avoided costs for vegetation management and habitat creation and maintenance were used to establish the value of managed grazing. If conversion is to be slowed or stopped and managed grazing promoted to protect the ecosystem services rangelands provide, this value could be compensated through

  10. Exploration of Possible Astroblemes in the Argentine Puna

    NASA Astrophysics Data System (ADS)

    Acevedo, R. D.; Alonso, R.; Rocca, M.; Klajnik, K.; Tálamo, E.

    2014-09-01

    Potential three new astrobleme sites have been detected by remote sensors and checked in situ in Argentine Puna: an elevated plateau that it has remained stable and invariable across long geological periods.

  11. Pheromone disruption of Argentine ant trail integrity

    USGS Publications Warehouse

    Suckling, D.M.; Peck, R.W.; Manning, L.M.; Stringer, L.D.; Cappadonna, J.; El-Sayed, A. M.

    2008-01-01

    Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. ?? 2008 Springer Science+Business Media, LLC.

  12. Assessment of LANDSAT for rangeland mapping, Rush Valley, Utah

    NASA Technical Reports Server (NTRS)

    Ridd, M. K.; Price, K. P.; Douglass, G. E.

    1984-01-01

    The feasibility of using LANDSAT MSS (multispectral scanner) data to identify and map cover types for rangeland, and to determine comparative condition of the ecotypes was assessed. A supporting objective is to assess the utility of various forms of aerial photography in the process. If rangelands can be efficiently mapped with Landsat data, as supported by appropriate aerial photography and field data, then uniform standards of cover classification and condition may be applied across the rangelands of the state. Further, a foundation may be established for long-term monitoring of range trend, using the same satellite system over time.

  13. Assessing transportation infrastructure impacts on rangelands: test of a standard rangeland assessment protocol

    USGS Publications Warehouse

    Duniway, Michael C.; Herrick, Jeffrey E.; Pyke, David A.; Toledo, David

    2010-01-01

    Linear disturbances associated with on- and off-road vehicle use on rangelands has increased dramatically throughout the world in recent decades. This increase is due to a variety of factors including increased availability of all-terrain vehicles, infrastructure development (oil, gas, renewable energy, and ex-urban), and recreational activities. In addition to the direct impacts of road development, the presence and use of roads may alter resilience of adjoining areas through indirect effects such as altered site hydrologic and eolian processes, invasive seed dispersal, and sediment transport. There are few standardized methods for assessing impacts of transportation-related land-use activities on soils and vegetation in arid and semi-arid rangelands. Interpreting Indicators of Rangeland Health (IIRH) is an internationally accepted qualitative assessment that is applied widely to rangelands. We tested the sensitivity of IIRH to impacts of roads, trails, and pipelines on adjacent lands by surveying plots at three distances from these linear disturbances. We performed tests at 16 randomly selected sites in each of three ecosystems (Northern High Plains, Colorado Plateau, and Chihuahuan Desert) for a total of 208 evaluation plots. We also evaluated the repeatability of IIRH when applied to road-related disturbance gradients. Finally, we tested extent of correlations between IIRH plot attribute departure classes and trends in a suite of quantitative indicators. Results indicated that the IIRH technique is sensitive to direct and indirect impacts of transportation activities with greater departure from reference condition near disturbances than far from disturbances. Trends in degradation of ecological processes detected with qualitative assessments were highly correlated with quantitative data. Qualitative and quantitative assessments employed in this study can be used to assess impacts of transportation features at the plot scale. Through integration with remote

  14. Medusahead in sagebrush steppe rangelands: Prevention, control, and revegetation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Medusahead is an exotic annual grass invading western rangelands. Medusahead invasion is particularly troublesome, because revegetation of invaded areas is difficult. This manuscript synthesizes the literature to provide recommendations for managing medusahead in sagebrush plant communities. Beca...

  15. Future scenarios of impacts to ecosystem services on California rangelands

    USGS Publications Warehouse

    Byrd, Kristin; Alvarez, Pelayo; Flint, Lorraine; Flint, Alan

    2014-01-01

    The 18 million acres of rangelands in the Central Valley of California provide multiple benefits or “ecosystem services” to people—including wildlife habitat, water supply, open space, recreation, and cultural resources. Most of this land is privately owned and managed for livestock production. These rangelands are vulnerable to land-use conversion and climate change. To help resource managers assess the impacts of land-use change and climate change, U.S. Geological Survey scientists and their cooperators developed scenarios to quantify and map changes to three main rangeland ecosystem services—wildlife habitat, water supply, and carbon sequestration. Project results will help prioritize strategies to conserve these rangelands and the ecosystem services that they provide.

  16. IMAGING SPECTROSCOPY FOR DETERMINING RANGELAND STRESSORS TO WESTERN WATERSHEDS

    EPA Science Inventory

    The Environmental Protection Agency is developing rangeland ecological indicators in twelve western states using advanced remote sensing techniques. Fine spectral resolution (hyperspectral) sensors, or imaging spectrometers, can detect the subtle spectral features that make veget...

  17. IMAGING SPECTROSCOPY FOR DETERMINING RANGELAND STRESSORS TO WESTERN WATERSHEDS

    EPA Science Inventory

    The Environmental Protection Agency is developing rangeland ecological indicators in eleven western states using advanced remote sensing systems. Fine spectral resolution (hyperspemal) sensors, or imaging spectrometers, can detect the subtle spectral features that makes vegetatio...

  18. An Optimization of the Maintenance Assets Distribution Network in the Argentine Air Force

    DTIC Science & Technology

    2015-03-26

    AN OPTIMIZATION OF THE MAINTENANCE ASSETS DISTRIBUTION NETWORK IN THE ARGENTINE AIR FORCE...copyright protection in the United States. AFIT-ENS-MS-15-M-152 AN OPTIMIZATION OF THE MAINTENANCE ASSETS DISTRIBUTION NETWORK IN THE ARGENTINE AIR...PUBLIC RELEASE; DISTRIBUTION UNLIMITED. AFIT-ENS-MS-15-M-152 AN OPTIMIZATION OF THE MAINTENANCE ASSETS DISTRIBUTION NETWORK IN THE ARGENTINE AIR

  19. Argentine nuclear development: capabilities and implications

    SciTech Connect

    Watson, C.A.

    1984-01-01

    Complacency was shattered in 1974 by the Indian explosion of a nuclear device developed from a civil nuclear program. The fear of nuclear weapon spread led the international system to consider the other states that could develop devices from what were assumed to be peaceful nuclear programs. Many states of the non-nuclear ranks, often the more developed states of the Third World, resented the nuclear suppliers weapon holders dictating to the developing states the types of technology that these states could handle. Some of these developing states had highly sophisticated nuclear programs that no longer rely on the suppliers for assistance. These states are using the options that their nuclear developments present in an attempt to alter the international system, or the balance of power, that has existed since the end of World War II. Argentina's nuclear program has become one of the most-sophisticated in the Third World. This work discusses the implications of the country's present capabilities as they affect Argentine actions in the foreign policy areas of nuclear commerce and the international nuclear weapons non-proliferation regime.

  20. An Integrated Social, Economic, and Ecologic Conceptual (ISEEC) Framework for Considering Rangeland Sustainability

    SciTech Connect

    Robert P. Breckenridge

    2009-08-01

    Currently, there is no standard method to assess the complex systems in rangeland ecosystems. Decision makers need baselines to create a common language of current rangeland conditions and standards for continued rangeland assessment. The Sustainable Rangeland Roundtable (SRR), a group of private and public organizations and agencies, has created a forum to discuss rangeland sustainability and assessment. The SRR has worked to integrate social, economic, and ecological disciplines related to rangelands and has identified a standard set of indicators that can be used to assess rangeland sustainability. As part of this process, SRR has developed a two-tiered conceptual framework from a systems perspective to study the validity of indicators and the relationships among them. The first tier categorizes rangeland characteristics into four states. The second tier defines processes affecting these states through time and space. The framework clearly shows that the processes affect and are affected by each other.

  1. An Integrated Social, Economic, and Ecologic Conceptual (ISEEC) framework for considering rangeland sustainability

    USGS Publications Warehouse

    Fox, W.E.; McCollum, D.W.; Mitchell, J.E.; Swanson, L.E.; Kreuter, U.P.; Tanaka, J.A.; Evans, G.R.; Theodore, Heintz H.; Breckenridge, R.P.; Geissler, P.H.

    2009-01-01

    Currently, there is no standard method to assess the complex systems in rangeland ecosystems. Decision makers need baselines to create a common language of current rangeland conditions and standards for continued rangeland assessment. The Sustainable Rangeland Roundtable (SRR), a group of private and public organizations and agencies, has created a forum to discuss rangeland sustainability and assessment. The SRR has worked to integrate social, economic, and ecological disciplines related to rangelands and has identified a standard set of indicators that can be used to assess rangeland sustainability. As part of this process, SRR has developed a two-tiered conceptual framework from a systems perspective to study the validity of indicators and the relationships among them. The first tier categorizes rangeland characteristics into four states. The second tier defines processes affecting these states through time and space. The framework clearly shows that the processes affect and are affected by each other. ?? 2009 Taylor & Francis Group, LLC.

  2. Perceptions of ranchers about medusahead (Taeniatherum caput-medusae (L.) Nevski) management on sagebrush steppe rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Medusahead (Taeniatherum caput-medusae (L.) Nevski) is an exotic annual grass invading rangelands in the western United States. Medusahead is a serious management concern because its decreases biodiversity, reduces livestock forage production, and degrades ecological function of rangelands. Despit...

  3. Very High Resolution Panoramic Photography to Improve Conventional Rangeland Monitoring 1994

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland monitoring often includes repeat photographs as a basis for documentation and although photographic equipment and electronics have been evolving rapidly, basic rangeland photo monitoring methods have changed little over time. Ground based digital photography is underutilized, especially s...

  4. Genetic diversity of Argentine isolates of feline immunodeficiency virus.

    PubMed

    Pecoraro, M R; Tomonaga, K; Miyazawa, T; Kawaguchi, Y; Sugita, S; Tohya, Y; Kai, C; Etcheverrigaray, M E; Mikami, T

    1996-09-01

    We report the nucleotide sequence and genetic diversity of part of the envelope (env) gene of four strains of feline immunodeficiency virus (FIV) isolated from Argentine domestic cats. The DNA encoding the V3 to V5 regions of the env gene of the FIV isolates were amplified by PCR, cloned and sequenced. Phylogenetic analysis revealed that the Argentine isolates did not cluster into a single group; one isolate clustered with subtype B FIV isolated in the USA and Japan, whereas the others formed a new cluster of FIV which might represent a prototype sequence for subtype E.

  5. State-and-transition model archetypes: a global taxonomy of rangeland change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    State and transition models (STMs) synthesize science-based and local knowledge to formally represent the dynamics of rangeland and other ecosystems. Mental models or concepts of ecosystem dynamics implicitly underlie all management decisions in rangelands and thus how people influence rangeland sus...

  6. Invasive rangeland plants in range and animal sciences and resources management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Comprising about 50% of the world’s land surface, rangelands are an important ecological and economic resource. Rangeland plant communities are changing. Even though the composition of plant communities in rangeland changes continually through the process of succession, in more recent years this c...

  7. Spatial predictions of cover attributes of rangeland ecosystems using regression kriging and remote sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sound rangeland management requires accurate information on rangeland condition over large landscapes. A commonly-applied approach to making spatial predictions of attributes related to rangeland condition (e.g., shrub or bare ground cover) from remote sensing is via regression between field and rem...

  8. New concentrated flow hydraulics equations for physically-based rangeland hydrology and erosion models

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We examined the hydraulics of concentrated flow using unconfined field experimental data over diverse rangeland landscapes, and developed new empirical prediction models of different rangeland concentrated flow hydraulic parameters, which can be applicable across a wide span of rangeland sites, soil...

  9. Rangelands: Changes to improve the quality and performance of an important SRM journal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2008, an effort to improve the quality and financial performance of the journal RANGELANDS was begun. Reviews by the Society for Range Management (SRM) Board of Directors (BOD) appointed RANGELANDS Task Force (RTF) and the Advisory Council identified aspects of RANGELANDS critical to membership s...

  10. Characteristics of concentrated flow hydraulics for rangeland ecosystems: implications for hydrologic modeling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Concentrated flow is often the dominant source of water erosion following disturbance on rangeland. Because of the lack of studies that explain the hydraulics of concentrated flow on rangelands, cropland-based equations have typically been used for rangeland hydrology and erosion modeling, leading t...

  11. PROCESS OF RECOVERING URANIUM

    DOEpatents

    Carter, J.M.; Larson, C.E.

    1958-10-01

    A process is presented for recovering uranium values from calutron deposits. The process consists in treating such deposits to produce an oxidlzed acidic solution containing uranium together with the following imparities: Cu, Fe, Cr, Ni, Mn, Zn. The uranium is recovered from such an impurity-bearing solution by adjusting the pH of the solution to the range 1.5 to 3.0 and then treating the solution with hydrogen peroxide. This results in the precipitation of uranium peroxide which is substantially free of the metal impurities in the solution. The peroxide precipitate is then separated from the solution, washed, and calcined to produce uranium trioxide.

  12. The Mindful Attention Awareness Scale (MAAS) in an Argentine Population

    ERIC Educational Resources Information Center

    Montes, Silvana Andrea; Ledesma, Rubén Daniel; García, Natalia Mariana; Poó, Fernando Martín

    2014-01-01

    The purpose of this study was to provide evidence of validity for the Mindful Attention Awareness Scale scores in an Argentine sample (Spanish-language version). Results indicated satisfactory psychometric properties (a one-factor structure, good item discrimination, high reliability, and significant correlations with additional measures). This…

  13. Different Argentine Rural Extensionists' Mindsets and Their Practical Implications

    ERIC Educational Resources Information Center

    Landini, Fernando

    2015-01-01

    Purpose: This paper reflects upon the practice of Argentine rural extensionists working in the extension public system through the process of identifying different rural extensionists' types of mindsets and comparing them with transfer of technology extension approach, dialogical processes of horizontal knowledge exchange, participatory…

  14. Climate impacts on agriculture: Implications for forage and rangeland production

    SciTech Connect

    Izaurralde, Roberto C.; Thomson, Allison M.; Morgan, Jack; Fay, Philip; Polley, Wayne; Hatfield, Jerry L.

    2011-04-19

    Projections of temperature and precipitation patterns across the United States during the next 50 years anticipate a 1.5 to 2°C warming and a slight increase in precipitation as a result of global climate change. There have been relatively few studies of climate change impacts on pasture and rangeland (grazingland) species compared to those on crop species, despite the economic and ecological importance of the former. Here we review the literature on pastureland and rangeland species to rising CO2 and climate change (temperature, and precipitation) and discuss plant and management factors likely to influence pastureland and rangeland responses to change (e.g., community composition, plant competition, perennial growth habit, seasonal productivity, and management methods). Overall, the response of pasture species to increased [CO2] is consistent with the general response of C3 and C4 type vegetation, although significant exceptions exist. Both pastureland and rangeland species should exhibit an acceleration of metabolism and development due to earlier onset of spring green-up and longer growing seasons. However, in the studies reviewed here, C3 pasture species increased their photosynthetic rates by up to 40% while C4 species exhibited no increase in photosynthesis. In general, it is expected that increases in [CO2] and precipitation would enhance rangeland net primary production (NPP) while increased air temperatures would either increase or decrease NPP. Much of this uncertainty in response is due to uncertain future projections of precipitation, both globally and regionally. For example, if annual precipitation changes little or declines, rangeland plant response to warming temperatures and rising [CO2] may be neutral or may decline due to increased water stress. This review reveals the need for comprehensive studies of climate change impacts on the pasture ecosystem including grazing regimes, mutualistic relationships (e.g., plant roots-nematodes; N

  15. Rangeland CEAP: An assessment of natural resources conservation service practices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The NRCS uses science-based technology to provide conservation planning and assistance to land owners and land operators to maintain productive lands and healthy ecosystems. Evaluating science-based literature on effectiveness of rangeland conservation practices is an important first step as it pro...

  16. Medusahead In Sagebrush Steppe Rangelands: Control, Restoration, And Prevention.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Medusahead is a non-native annual grass that is degrading sagebrush rangelands. However, information on its management is not widely available to land managers. We compiled results from previous studies to provide information on controlling, restoring, and preventing medusahead infestations in sag...

  17. Integrated approach to cheatgrass suppression on great basin rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cheatgrass (Bromus tectorum), native to central Eurasia, is a highly invasive annual grass that has invaded millions of hectares of rangelands throughout the Intermountain West. Cheatgrass has revolutionized secondary succession by providing a fine-textured, early-maturing fuel that increases the c...

  18. Revegetating medusahead-invaded sagebrush rangelands in the Intermountain West

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Revegetation of medusahead-invaded rangeland is needed to increase forage production, decrease the risk of wildfires, and improve wildlife habitat. Successful revegetation starts with effective control of medusahead. Prescribed burning followed by a fall application of a pre-emergent herbicide has...

  19. Revegetating medusahead-invaded sagebrush rangelands in the intermountain west

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Revegetation of medusahead-invaded rangeland is needed to increase forage production, decrease the risk of wildfires, and improve wildlife habitat. Successful revegetation starts with effective control of medusahead. Prescribed burning followed by a fall application of a pre-emergent herbicide has...

  20. Financial incentives: Possible options for sustainable rangeland management?

    PubMed

    Louhaichi, Mounir; Yigezu, Yigezu A; Werner, Jutta; Dashtseren, Lojoo; El-Shater, Tamer; Ahmed, Mohamed

    2016-09-15

    Large-scale mismanagement of natural resources emanating from lack of appropriate policies and regulatory framework is arguably one of the reasons that led to resource degradation and poor livelihoods in many countries in the Middle East and North Africa (MENA) region. Sustainable rangeland management practices (SRMPs) are considered to be a solution to feed shortages and rangeland degradation. However, the scope for SRMP adoption, has been a subject of debate. Using a case study from Syria and the application of the Minimum Data Analysis method (TOA-MD), this paper provides empirical evidence for ensuring wider adoption of SRMP. The paper argues that the introduction of financial incentives in the form of payments for agricultural-environmental services can increase the economic viability and enhance the adoption of SRMPs and is a better alternative to the unsustainable state subsidies for fodder purchases and barley cultivation on rangelands. Model results indicate that further investment in reasearch toward generating low cost technologies and tailored governance strategies including a financial incentive system would lead to better management of rangelands and improve livelihoods in the Syrian Badia. These findings are valuable for policy makers, donors as well as development and extension practitioners in the MENA region as they can better inform future courses of actions.

  1. Brush management as a rangeland conservation strategy: A critical evaluation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the most striking land cover changes on rangelands worldwide over the past 150 years has been the proliferation of trees and shrubs at the expense of perennial grasses. Woody plant encroachment represents a threat to grassland, shrub-steppe and savanna ecosystems and the plants and animals n...

  2. Making soil health a part of rangeland management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil health describes the ability of a soil to function at its potential, specifically “The capacity of a soil to function as a vital, living ecosystem that sustains plants, animals and humans”. The objectives of this paper are to 1) contextualize rangeland soil health by examining the common defini...

  3. Development of a UAV rangeland remote sensing capability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Starting in 2000, experiments have been conducted at the Jornada Experimental Range near Las Cruces, NM to evaluate the utility of Unmanned Aerial Vehicles (UAVs) for applications on arid rangelands. When compared to all types of remote sensing research ongoing at Jornada and other locations, UAVs h...

  4. A site-based approach to delivering rangeland ecosystem services

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland ecosystems are capable of providing an array of ecosystem services important to the wellbeing of society. Some of these services (e.g. meat, fibre) are transported to markets and their quantity, quality and value are established via a set of widely accepted standards. Other services (e.g. ...

  5. Opportunities for increasing utility of models for rangeland management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A tremendous need exists for ecosystem models to assist in rangeland management, but the utility of models developed to date has been minimal for enterprise-level decision making. Three areas in which models have had limited effectiveness for land managers are 1) addressing contemporary needs associ...

  6. Cattle as ecosystem engineers: New grazing management enhances rangeland biodiversity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A confluence of factors has shaped the composition and structure of vegetation on rangelands in the American West. These factors include climate, soils, topography, history of grazing and fire (both wildfire and prescribed fire) as well as legacy effects from prior land management practices. Despite...

  7. Rangeland Ecosystem Services: Nature's Supply and Human's Demands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ecosystem services are the benefits that society receives from nature and they include the regulation of climate, the pollination of crops, the provisioning of intellectual inspiration and recreational environment, as well as many essential goods such as food, fiber, and wood. Rangeland ecosystem se...

  8. Sound management may sequester methane in grazed rangeland ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Considering their contribution to global warming, the sources and sinks of methane (CH4) should be accounted when undertaking a greenhouse gas inventory for grazed rangeland ecosystems. The aim of this study was to evaluate the mitigation potential of current ecological management programs implement...

  9. Importance of shrub restoration on great basin rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The recognition of brush species and the browse these plants provide as an important component of rangeland production was often overlooked in land management for some time. Even after the birth of range management in the early twentieth century, herbaceous species were considered the basic componen...

  10. The importance of seed germination in rangeland research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA, Agricultural Research Service (ARS)/ Great Basin Rangelands Research Unit, Wildland Seed Laboratory, located in Reno, NV, has been studying seed germination for the past 40 years. The wildland seed laboratory has collected, processed, and quantified germination characteristics of hundreds...

  11. Parameterization of erodibility in the Rangeland Hydrology and Erosion Model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The magnitude of erosion from a hillslope is governed by the availability of sediment and connectivity of runoff and erosion processes. For undisturbed rangelands, sediment is primarily detached and transported by rainsplash and sheetflow (splash-sheet) processes in isolated bare batches, but sedime...

  12. Rangelands, pastoralists and governments: interlinked systems of people and nature.

    PubMed Central

    Walker, Brian H; Janssen, Marco A

    2002-01-01

    We analyse commercially operated rangelands as coupled systems of people and nature. The biophysical components include: (i) the reduction and recovery of potential primary production, reflected as changes in grass production per unit of rainfall; (ii) changes in woody plants dependent on the grazing and fire regimes; and (iii) livestock and wool dynamics influenced by season, condition of the rangeland and numbers of wild and feral animals. The social components include the managers, who vary with regard to a range of cognitive abilities and lifestyle choices, and the regulators who vary in regard to policy goals. We compare agent-based and optimization models of a rangeland system. The agent-based model leads to recognition that policies select for certain management practices by creating a template that governs the trajectories of the behaviour of individuals, learning, and overall system dynamics. Conservative regulations reduce short-term loss in production but also restrict learning. A free-market environment leads to severe degradation but the surviving pastoralists perform well under subsequent variable conditions. The challenge for policy makers is to balance the needs for learning and for preventing excessive degradation. A genetic algorithm model optimizing for net discounted income and based on a population of management solutions (stocking rate, how much to suppress fire, etc.) indicates that robust solutions lead to a loss of about 40% compared with solutions where the sequence of rainfall was known in advance: this is a similar figure to that obtained from the agent-based model. We conclude that, on the basis of Levin's three criteria, rangelands with their livestock and human managers do constitute complex adaptive systems. If this is so, then command-and-control approaches to rangeland policy and management are bound to fail. PMID:12079532

  13. Recovering plant biodiversity

    PubMed Central

    2011-01-01

    Studying recovering plant biodiversity on Mount Pinatubo may provide valuable insights that improve our understanding of recovery of other ecosystems following disturbances of all types. Ongoing sheet and rill erosion coupled with mass waste events in the unstable pyroclastic flow deposits persist, effectively re-setting primary succession at micro-landscape scale without affecting habitat level diversity. Spatial factors and micro-habitat diversity may exert more control over continued succession as the riparian systems become more deeply dissected and complex. The number of taxa within functional groups and conservation concerns are botanical issues that deserve further research. PMID:22019638

  14. [Argentine consensus on the treatment of bipolar disorders].

    PubMed

    Vázquez, Gustavo Héctor; Strejilevich, Sergio; García Bonetto, Gerardo; Cetkovich-Bakmas, Marcelo; Zaratiegui, Rodolfo; Lagomarsino, Alejandro; Goldchluk, Aníbal; Kalina, Eduardo; Herbst, Luis; Gutiérrez, Benigno

    2005-01-01

    The consensus guidelines of argentine experts in the treatment of bipolar disorders are the result of three days of work of the 10 main local experts under the organization of the Argentine Association of Biological Psychiatry (AAPB). It was adopted a mixed criterion for its preparation: all the recent data of the evidence medicine based published until now were discussed and were balanced with the knowledge acquired from clinical experience of the local experts on the bipolar field. It presents general recommendations and suggested therapeutic sequences for the phase of maintenance, the manic/hypomanic or mixed episode and the depressive episode. These have been divided according to the classification in type I and II; with or without rapid cycling. Since the group of experts identified the delay and miss-diagnoses like the most important barrier for a suitable treatment enclosed a series of recommendations for differential diagnosis of bipolar disorders.

  15. Fast and Flexible: Argentine Ants Recruit from Nearby Trails

    PubMed Central

    Flanagan, Tatiana P.; Pinter-Wollman, Noa M.; Moses, Melanie E.; Gordon, Deborah M.

    2013-01-01

    Argentine ants (Linepithema humile) live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources. PMID:23967129

  16. Fast and flexible: argentine ants recruit from nearby trails.

    PubMed

    Flanagan, Tatiana P; Pinter-Wollman, Noa M; Moses, Melanie E; Gordon, Deborah M

    2013-01-01

    Argentine ants (Linepithema humile) live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources.

  17. Malvinas: the Argentine Perspective of the Falkland’s Conflict

    DTIC Science & Technology

    2010-05-01

    such a way that: “Neither British military nor local civilians should be killed during the entire Argentine military operation over own territory .”3...Giachino knew that that mission went beyond the simple seizure of territory and that any loss of life would hurt the post-war negotiations that...Informe Oficial del Ejercito Argentino Tomo II - Conflicto Malvinas (Buenos Aires- Argentina: Estado Mayor General del Ejercito Argentino 1983): Annex 6. 5

  18. Argentine Population Genetic Structure: Large Variance in Amerindian Contribution

    PubMed Central

    Seldin, Michael F.; Tian, Chao; Shigeta, Russell; Scherbarth, Hugo R.; Silva, Gabriel; Belmont, John W.; Kittles, Rick; Gamron, Susana; Allevi, Alberto; Palatnik, Simon A.; Alvarellos, Alejandro; Paira, Sergio; Caprarulo, Cesar; Guillerón, Carolina; Catoggio, Luis J.; Prigione, Cristina; Berbotto, Guillermo A.; García, Mercedes A.; Perandones, Carlos E.; Pons-Estel, Bernardo A.; Alarcon-Riquelme, Marta E.

    2011-01-01

    Argentine population genetic structure was examined using a set of 78 ancestry informative markers (AIMs) to assess the contributions of European, Amerindian, and African ancestry in 94 individuals members of this population. Using the Bayesian clustering algorithm STRUCTURE, the mean European contribution was 78%, the Amerindian contribution was 19.4%, and the African contribution was 2.5%. Similar results were found using weighted least mean square method: European, 80.2%; Amerindian, 18.1%; and African, 1.7%. Consistent with previous studies the current results showed very few individuals (four of 94) with greater than 10% African admixture. Notably, when individual admixture was examined, the Amerindian and European admixture showed a very large variance and individual Amerindian contribution ranged from 1.5 to 84.5% in the 94 individual Argentine subjects. These results indicate that admixture must be considered when clinical epidemiology or case control genetic analyses are studied in this population. Moreover, the current study provides a set of informative SNPs that can be used to ascertain or control for this potentially hidden stratification. In addition, the large variance in admixture proportions in individual Argentine subjects shown by this study suggests that this population is appropriate for future admixture mapping studies. PMID:17177183

  19. Paleomagnetic confirmation of the Laurentian origin of the Argentine Precordillera

    NASA Astrophysics Data System (ADS)

    Rapalini, A. E.; Astini, R. A.

    1998-02-01

    Several recent tectonic models have portrayed the Argentine Precordillera has been recently portrayed as an Early Paleozoic Laurentian derived exotic terrane now found in southwestern South America. These models have primarily been based on strong biogeographic and stratigraphic evidence, however, no paleomagnetic data have previously been available to independently test them. A paleomagnetic study was, therefore, carried out on the Early Cambrian Cerro Totora Formation, exposed in the northern reaches of the Argentine Precordillera. After stepwise thermal demagnetization a pre-folding remanence was identified in ten sites of this formation, yielding a paleomagnetic pole (CT) at 37.0°N, 314.1°E, A95=5.8°. This pole is not consistent with the latest Proterozoic-Early Paleozoic apparent polar wander path for Gondwana, but it agrees with the Early Cambrian Section of the Laurentian path if the Argentine Precordillera is positioned as the conjugate margin of the Ouachita embayment in southeast Laurentia. This result confirms that the Precordillera is an allochthonous terrane derived from Laurentia in Cambrian times, that was later accreted to Gondwana, probably in Middle Ordovician times.

  20. [Behavior of Argentine lymphocytic choriomeningitis virus strains in rodents].

    PubMed

    Saavedra, María del Cármen; Ambrosio, Ana M; Riera, Laura; Sabattini, Marta S

    2007-01-01

    The activity of LCM virus was first reported in Argentina at the beginning of the seventies and only five strains have been isolated from rodents Mus domesticus and two from humans. The objective of this paper was to find differential biological characteristics of Argentine strains of LCM virus comparing them in relation to the historical strains WE and Armstrong. Regarding the results obtained in tissue culture, when L 929 cells were used, plaque forming units (PFU) were obtained with human and mouse strains, whilst on Vero cells only human strains developed PFU. Differentials characteristics of historical and Argentine strain's plates were not found, neither differences related to the strain's origin. Neither historical nor Argentine strains were lethal to new-born mice giving a persistent infection, that was demonstrated when we inoculated new-born mouse by intracranial route with different strains of LCM virus and virus was isolated from brains harvested at different days post inoculation. The only exception was Cba An 13065 strain that exhibited virulence in new-born mice, only with 0.026 PFU was obtained 1 DL50. All the strains resulted lethal to adult mice. The mouse strains were more virulent than human strains, being Cba An 13065 the most virulent. These results demonstrate a different behavior in tissue culture between human and mouse strains and allow the identification of virulence markers by intracranial inoculation into new-born or adult mice.

  1. State of knowledge about energy development impacts on North American rangelands: An integrative approach.

    PubMed

    Kreuter, Urs P; Iwaasa, Alan D; Theodori, Gene L; Ansley, R James; Jackson, Robert B; Fraser, Lauchlan H; Naeth, M Anne; McGillivray, Susan; Moya, Edmundo Garcia

    2016-09-15

    To reduce dependence on foreign oil reserves, there has been a push in North America to develop alternative domestic energy resources. Relatively undeveloped renewable energy resources include biofuels and wind and solar energy, many of which occur predominantly on rangelands. Rangelands are also key areas for natural gas development from shales and tight sand formations. Accordingly, policies aimed at greater energy independence are likely to affect the delivery of crucial ecosystem services provided by rangelands. Assessing and dealing with the biophysical and socio-economic effects of energy development on rangeland ecosystems require an integrative and systematic approach that is predicated on a broad understanding of diverse issues related to energy development. In this article, we present a road map for developing an integrative assessment of energy development on rangelands in North America. We summarize current knowledge of socio-economic and biophysical aspects of rangeland based energy development, and we identify knowledge gaps and monitoring indicators to fill these knowledge gaps.

  2. Process for recovering uranium

    DOEpatents

    MacWood, G. E.; Wilder, C. D.; Altman, D.

    1959-03-24

    A process useful in recovering uranium from deposits on stainless steel liner surfaces of calutrons is presented. The deposit is removed from the stainless steel surface by washing with aqueous nitric acid. The solution obtained containing uranium, chromium, nickel, copper, and iron is treated with an excess of ammonium hydroxide to precipitnte the uranium, iron, and chromium and convert the nickel and copper to soluble ammonio complexions. The precipitated material is removed, dried and treated with carbon tetrachloride at an elevated temperature of about 500 to 600 deg C to form a vapor mixture of UCl/ sub 4/, UCl/sub 5/, FeCl/sub 3/, and CrCl/sub 4/. The UCl/sub 4/ is separated from this vapor mixture by selective fractional condensation at a temperature of about 500 to 400 deg C.

  3. PROCESS FOR RECOVERING URANIUM

    DOEpatents

    MacWood, G.E.; Wilder, C.D.; Altman, D.

    1959-03-24

    A process is described for recovering uranium from deposits on stainless steel liner surfaces of calutrons. The deposit is removed from the stainless steel surface by washing with aqueous nitric acid. The solution obtained containing uranium, chromium, nickels copper, and iron is treated with excess of ammonium hydroxide to precipitatc the uranium, irons and chromium and convert thc nickel and copper to soluble ammonia complexions. The precipitated material is removed, dried, and treated with carbon tetrachloride at an elevated temperature of about 500 to 600 deg C to form a vapor mixture of UCl/sub 4/, UCl/sub 5/, FeCl/ sub 3/, and CrCl/sub 4/. The UCl/sub 4/ is separated from this vapor mixture by selective fractional condensation at a temprrature of about 300 to400 deg C.

  4. METHOD OF RECOVERING THORIUM

    DOEpatents

    Fisher, R.W.

    1957-12-10

    A method is described for recovering thorium from impurities found in a slag containing thorium and said impurities, comprising leaching a composition containing thorium with water, removing the water solution, treating the residue with hydrochloric acid, separating the solution from the insoluble residue, adjusting its acidity to 1 to 3 normal, adding oxalic acid, and thereafter separating the precipitated thorium oxalate digesting the residue from the hydrochloric acid treatment with a strong solution of sodium hydroxide at an elevated temperature, removing said solution and treating the insoluble residue with hydrochloric acid, separating the solution from the insoluble residue, adjusting the acidity of this solution to 1 to 3 normal, adding nitric acid to oxidize the iron present, adding oxalic acid and thereafter separating the thorium oxalate thus precipitated.

  5. The swift fox in rangeland and cropland in western Kansas: Relative abundance, mortality, and body size

    USGS Publications Warehouse

    Matlack, R.S.; Gipson, P.S.; Kaufman, D.W.

    2000-01-01

    We assessed suitability of cropland and shortgrass rangeland for swift foxes (Vulpes velox) in western Kansas. Relative abundance and survival were similar for foxes in rangeland and cropland. Mortality resulting from non-traumatic causes, coyotes, and motor vehicles differed significantly between habitats. Predation by coyotes, motor vehicles, and non-traumatic causes were responsible for 45%, 36%, and 18%, respectively, of 11 deaths in rangeland and 20%, 10%, and 70%, respectively, of 10 deaths in cropland. Swift foxes in rangeland were larger and in better condition than those in cropland. Males were larger than females based on mass, standardized mass (mass/body length), body length, hindfoot length, and ear length.

  6. Giant mudwaves in the Northern Argentine Basin: born and buried by bottom currents

    NASA Astrophysics Data System (ADS)

    Borisov, Dmitrii; Murdmaa, Ivar; Ivanova, Elena; Levchenko, Oleg

    2014-05-01

    New sedimentary records and very high resolution seismic profiles collected during four cruises of the RV "Akademik Ioffe" (2011-2013) were correlated with seismic, multibeam and coring data obtained during cruises of the RV "Robert Conrad", "Knorr", "Meteor". A complex analysis of the geological-geophysical data revealed an extensive field of giant mudwaves (48 000 km2) in the northwestern Argentine Basin, South Atlantic. The symmetric waves up to 60 m in height and 4000 m in wavelength are oriented roughly parallel to contours. They partly cover the Santa Catarina Plateau and extend through the Santos Basin to the Sao Paulo Plateau. The mudwaves field is traced at the depth range from 3400 to 4000 m and divided into buried (northern) and non-buried (southern) parts. The non-buried sediment waves cover the surface of the huge drift in the Santa Catarina Plateau. The wave height increases from the drift summit to its flanks and decreases at the foot. Two cores retrieved from the drift top and its northern flank recovered muddy contourites with a greater amount of silt-size material in the core from the drift flank. The age of the recovered sediments is at least 130 ka. In the northern Santos basin, the sediment waves are buried under a large lens-like sediment body (drift?) inclined at the margins. Cores obtained from the buried part of the mudwaves field recovered an intercalation of hemipelagic clay and silty-clay contourite. The age of recovered sediments does not exceed 150 ka (Bleil et al., 1993). Contourites deposition in the study area is related to the activity of the Antarctic bottom water (AABW) contour current. The AABW flow is considered to be divided into two branches by the Santa Catarina Plateau. We suggest that this topographic obstacle causes a flow velocity increase. Wave height and grain-size variations indicate higher bottom current velocities at the plateau flanks and relative tranquil conditions at the flat summit of the plateau. The symmetric

  7. A Framework for Improving Integrative Factors in C3I Systems of the Argentine Army

    DTIC Science & Technology

    1991-03-01

    improving integrative factors in C3I systems of the Argentine Army by Eduardo Alfredo Trotta Major, Argentine Army Ingeniero Militar , Escuela...Library, Code 52 2 Naval Postgraduate School Monterey, CA 93943-5002 3. Estado Mayor General del Ej~rcito Argentino 3 Direcci6n de Comunicaciones

  8. Rangeland health attributes and indicators for qualitative assessment

    USGS Publications Warehouse

    Pyke, David A.; Herrick, J.E.; Pellant, Mike

    2002-01-01

    Panels of experts from the Society for Range Management and the National Research Council proposed that status of rangeland ecosystems could be ascertained by evaluating an ecological site's potential to conserve soil resources and by a series of indicators for ecosystem processes and site stability. Using these recommendations as a starting point, we developed a rapid, qualitative method for assessing a moment-in-time status of rangelands. Evaluators rate 17 indicators to assess 3 ecosystem attributes (soil and site stability, hydrologic function, and biotic integrity) for a given location. Indicators include rills, water flow patterns, pedestals and terracettes, bare ground, gullies, wind scour and depositional areas, litter movement, soil resistance to erosion, soil surface loss or degradation, plant composition relative to infiltration, soil compaction, plant functional/structural groups, plant mortality, litter amount, annual production, invasive plants, and reproductive capability. In this paper, we detail the development and evolution of the technique and introduce a modified ecological reference worksheet that documents the expected presence and amount of each indicator on the ecological site. In addition, we review the intended applications for this technique and clarify the differences between assessment and monitoring that lead us to recommend this technique be used for moment-in-time assessments and not be used for temporal monitoring of rangeland status. Lastly, we propose a mechanism for adapting and modifying this technique to reflect improvements in understanding of ecosystem processes. We support the need for quantitative measures for monitoring rangeland health and propose some measures that we believe may address some of the 17 indicators.

  9. Recover bromine on site

    SciTech Connect

    Schubert, P.; Mahajan, S.; Beatty, R.D.; Rostrup-Nielsen, T.; Schubert, D.W.; Lu, Phat Tan

    1993-04-01

    Chemists have long recognized the importance of recovering bromine from waste streams, and attempts to do so catalytically date back more than 50 years. Although the early interest in bromine recovery was driven primarily by economics, increased environmental pressures are providing additional incentives to recycle this element. As the acceptability of discharging wastes into the environment decreases, the cost of doing so increases, creating a need for alternative handling. The authors interest in waste bromine recovery was driven by both economic and environmental factors. In their evaluation of a research program that included a bromination step as part of a synthesis process, Catalytica researchers found that the process would be feasible commercially only if the waste HBr produced were recycled on site to bromine. A nonbromine route was eventually adopted for this particular research program, but the need for an economical and environmentally sound process for recycling HBr to bromine was recognized. The development of this process became a project in its own right. This process eliminates the need to form and ship aqueous sodium bromide offsite. It converts the waste HBr directly to bromine by catalytic oxidation.

  10. PROCESS OF RECOVERING URANIUM

    DOEpatents

    Kilner, S.B.

    1959-12-29

    A method is presented for separating and recovering uranium from a complex mixure of impurities. The uranium is dissolved to produce an aqueous acidic solution including various impurities. In accordance with one method, with the uranium in the uranyl state, hydrogen cyanide is introduced into the solution to complex the impurities. Subsequently, ammonia is added to the solution to precipitate the uraniunn as ammonium diuranate away from the impurities in the solution. Alternatively, the uranium is precipitated by adding an alkaline metal hydroxide. In accordance with the second method, the uranium is reduced to the uranous state in the solution. The reduced solution is then treated with solid alkali metal cyanide sufficient to render the solution about 0.1 to 1.0 N in cyanide ions whereat cyanide complex ions of the metal impurities are produced and the uranium is simultaneously precipituted as uranous hydroxide. Alternatively, hydrogen cyanide may be added to the reduced solution and the uranium precipitated subsequently by adding ammonium hydroxide or an alkali metal hydroxide. Other refinements of the method are also disclosed.

  11. Decision methodology for the resource utilization of rangeland watersheds

    SciTech Connect

    Khalili, D.

    1986-01-01

    Degradation of rangeland resources leading to the desertification process is viewed in terms of human and climatic influences. While climatic impacts are important, resource utilization as practiced by man is the major cause of desertification. A multi-objective decision methodology developed here is intended for the analysis of alternative management plans of rangeland watersheds under climatic variability. First, a system model is employed to portray the dynamics of a rangeland as it would respond to climatic changes and different grazing intensities. This approach allows for an interaction of inputs such as rainfall, solar radiation, and temperature with the sate of the system which is a range condition index, and with outputs such as production and sediment yield. A simulation package is developed to implement the system model by actually using available data and providing some output values for production and sediment yield. At this stage a number of alternative management plans are identified. The information obtained from the simulation as well as other information of interest are represented by performance criteria, leading to an array of alternative versus criteria. Then, management plans need to be evaluated as they would impact the criteria. A multi-objective decision-making technique is selected to perform the analysis for an identification of preferred management alternatives.

  12. Assessing the impacts of livestock production on biodiversity in rangeland ecosystems.

    PubMed

    Alkemade, Rob; Reid, Robin S; van den Berg, Maurits; de Leeuw, Jan; Jeuken, Michel

    2013-12-24

    Biodiversity in rangelands is decreasing, due to intense utilization for livestock production and conversion of rangeland into cropland; yet the outlook of rangeland biodiversity has not been considered in view of future global demand for food. Here we assess the impact of future livestock production on the global rangelands area and their biodiversity. First we formalized existing knowledge about livestock grazing impacts on biodiversity, expressed in mean species abundance (MSA) of the original rangeland native species assemblages, through metaanalysis of peer-reviewed literature. MSA values, ranging from 1 in natural rangelands to 0.3 in man-made grasslands, were entered in the IMAGE-GLOBIO model. This model was used to assess the impact of change in food demand and livestock production on future rangeland biodiversity. The model revealed remarkable regional variation in impact on rangeland area and MSA between two agricultural production scenarios. The area of used rangelands slightly increases globally between 2000 and 2050 in the baseline scenario and reduces under a scenario of enhanced uptake of resource-efficient production technologies increasing production [high levels of agricultural knowledge, science, and technology (high-AKST)], particularly in Africa. Both scenarios suggest a global decrease in MSA for rangelands until 2050. The contribution of livestock grazing to MSA loss is, however, expected to diminish after 2030, in particular in Africa under the high-AKST scenario. Policies fostering agricultural intensification can reduce the overall pressure on rangeland biodiversity, but additional measures, addressing factors such as climate change and infrastructural development, are necessary to totally halt biodiversity loss.

  13. Gas-Phase Intramolecular Cyclization of Argentinated N-Allylbenzamides

    NASA Astrophysics Data System (ADS)

    Sun, Hezhi; Chai, Yunfeng; Jin, Zhe; Sun, Cuirong; Pan, Yuanjiang

    2015-05-01

    The fragmentations of argentinated N-allylbenzamides have been exhaustively studied through collision-induced dissociation and through deuterium labeling. The intriguing elimination of AgOH is certified as the consequence of intramolecular cyclization between terminal olefin and carbonyl carbon following proton transfer to carbonyl oxygen, rather than simple enolization of amide. Linear free energy correlations and density functional theory (DFT) calculations were performed to understand the competitive relationship between AgOH loss and AgH loss, which results from the 1,2-elimination of α-hydrogen (to the amido nitrogen) with the silver.

  14. Response to Barnes et al. Letter to the Editor (reference to Bracy Knight et al. 2011 paper in Rangelands)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our original article “Cross-fencing on private US rangelands: financial costs and producer risks” (Bracy Knight et al. 2011 Rangelands 33(2):41-44), demonstrated that producers incur high initial and continuing long-term costs associated with cross-fencing rangelands. While these costs can be partia...

  15. Using the best available data: integrating field data and remote sensing imagery to monitor rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Monitoring of rangelands poses significant challenges to land managers due to broad extent and many uses of rangelands. The Bureau of Land Management’s (BLM) Assessment, Inventory, and Monitoring (AIM) program seeks to efficiently collect standard, quantitative monitoring data which is collected onc...

  16. Evaluation of indigenous Lotus species for the western USA for rangeland revegetation and restoration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Semiarid rangelands in the western USA are facing serious challenges related to past mismanagement, invasive weedy species, wildfires, and climatic change. Leguminous forbs that are native to the western USA are of interest for rangeland revegetation and restoration because they provide biologicall...

  17. The 'range problem' after a century of rangeland science: New research themes for altered landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rangeland science profession in the United States has its roots in the widespread overgrazing and concurrent severe droughts of the late 19th Century. These drivers contributed to rangeland resource degradation especially in the American Southwest—what E. O. Wooton (1908) called "The Range Probl...

  18. Application of the Rangeland Hydrology and Erosion Model to Ecological Site Descriptions and Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The utility of Ecological Site Descriptions (ESDs) and State-and-Transition Models (STMs) concepts in guiding rangeland management hinges on their ability to accurately describe and predict community dynamics and the associated consequences. For many rangeland ecosystems, plant community dynamics ar...

  19. Hydrologic ramifications of an increased role of wildland fire across the rangeland-dry forest continuum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The increased role of wildland fire across the rangeland-dry forest continuum in the western United States (US) presents landscape-scale consequences relative runoff and erosion. Much of the Intermountain West now exists in a state in which rangeland and woodland wildfires stimulated by invasive che...

  20. Evaluation of Utah trefoil collections for rangeland restoration in the southern Great Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wildfires, weed invasion, and various other land disturbances are common in rangeland ecosystems of the Intermountain Region in the western U.S. Revegetation/restoration may be required on many of these rangelands to improve degraded conditions, speed recovery, and minimize soil erosion. Legumes n...

  1. Winter grazing decreases wildfire risk, severity, and behavior in semi-arid sagebrush rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wildfires are an ecological and economic risk for many semi-arid rangelands which has resulted in increased pressure for pre-suppression management of fuels. In rangelands, fuel management treatment options are limited by costs. We evaluated winter grazing as a tool to manage fuels and alter fire ...

  2. Editorial: a scientifically rigorous and user-friendly Rangeland Ecology & Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland Ecology and Management (REM) is the premier journal for communication of science-based knowledge and for fostering both innovation and rigor in our stewardship of the world’s rangelands. REM is critical to the mission of the Society for Range Management and has had increasing scientific im...

  3. Pilot Study for an Assessment of Vegetation Structure for Steppe Rangelands of Central Anatolia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the last fifty years, rangelands in the Central Anatolian Region of Turkey have been converted to cropping lands, which has negatively accelerated vegetation change, resulting in overgrazing, poor condition and productivity. In these steppe rangelands, to develop a rational basis for making resto...

  4. Plant/life form considerations in the rangeland hydrology and erosion model (RHEM)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resilience of rangeland to erosion has largely been attributed to adequate plant cover; however, plant life/growth form, and individual species presence can have a dramatic effect on hydrologic and erosion dynamics on rangelands. Plant life/growth form refers to genetic tendency of a plant to grow i...

  5. Development of North American forb plant materials for rangeland revegetation and restoration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant materials development for Intermountain rangelands is a primary mission of the USDA-ARS Forage and Range Research Laboratory. Currently there is a significant demand for North American forbs (including legumes) for rangeland revegetation and restoration in the Great Basin, but commercial quan...

  6. Heat dosage and oviposition depth influence egg mortality of two common rangeland grasshopper species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland fire is a common naturally occurring event and management tool, with the amount and structure of biomass controlling transfer of heat belowground. Temperatures grasshopper eggs are exposed to during rangeland fires are mediated by species specific oviposition traits. This experiment examin...

  7. Unmanned aerial vehicle-based remote sensing for rangeland assessment, monitoring, and management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland comprises as much as 70% of the Earth’s land surface area. Much of this vast space is in very remote areas that are expensive and often impossible to access on the ground. Unmanned Aerial Vehicles (UAVs) have great potential for rangeland management. UAVs have several advantages over satel...

  8. Development of an operational UAV / remote sensing capability for rangeland management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland comprises approximately 70% of the Earth’s land surface area. Much of this vast space is in very remote areas with difficult access. Unmanned Aerial Vehicles (UAVs) have great potential for rangeland management applications. UAVs have several advantages over satellites and piloted aircr...

  9. Collection and Domestication of Rangeland Plant Species with Emphasis on Mongolia and China

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Changing economic and social conditions are threatening plant diversity on rangelands in Mongolia and China. Teams of collaborating scientists from the U.S.A., Mongolia, and China collected seed of rangeland plant species in Mongolia and Inner Mongolia, China, to preserve plant biodiversity from th...

  10. Techniques for Assessing the Environmental Outcomes of Conservation Practices Applied to Rangeland Watersheds

    EPA Science Inventory

    Grazing lands are the most dominant land cover type in the United States, with approximately 311.7 Mha being defined as rangelands (Mitchell 2000). Approximately 53% (166.2 Mha) of the nation’s rangelands (USDA 2009) are owned and managed by the private sector, while approximat...

  11. Concentrated flow erodibility for physically-based erosion models: temporal variability in disturbed and undisturbed rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current physically based overland flow erosion models for rangeland application do not separate disturbed and undisturbed conditions in modeling concentrated flow erosion. In this study, concentrated flow simulations on disturbed and undisturbed rangelands were used to estimate the erodibility and t...

  12. Estimating rangeland runoff, soil erosion, and salt mobility and transport processes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over 55% of sediment and salts entering the Colorado River are derived from accelerated soil erosion from federal rangelands with damages estimated to be $385 million per year. About 55% of the loading is derived from rangelands. This suggests a significant potential to reduce dissolved-solids loa...

  13. Rangeland management strategies for adapting to climatic variability: Enhancing the positive and mitigating the negative effects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland management strategies for adapting to climatic variability are needed to reduce enterprise risk, increase resilience of rangeland/grassland ecosystems and deliver sustainable provision of ecosystem goods (e.g., livestock production) and services (e.g., wildlife habitat) from western North ...

  14. Earth stewardship on rangelands: Coping with ecological, economic, and political marginality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangelands encompass 30-40 percent of Earth's land surface and support 1-2 billion people. Their predominant use is extensive livestock production by pastoralists and ranchers. But rangelands are characterized by ecological, economic, and political marginality, and higher-value, more intensive land ...

  15. Cooperative prevention systems to protect rangelands from the spread of invasive plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Invasive plants continue to spread and impact rangelands in the western United States. Fortunately, many rangeland ecosystems still remain invasive weed-free.Cooperative prevention systems can safeguard these remaining areas. Local-level weed prevention areas (WPAs) prioritize prevention in the larg...

  16. AGWA: The Automated Geospatial Watershed Assessment Tool to Inform Rangeland Management

    EPA Science Inventory

    Do you want a relatively easy to use tool to assess rangeland soil and water conservation practices on rangeland erosion that is specifically designed to use ecological information? New Decision Support Tools (DSTs) that are easy-to-use, incorporate ecological concepts and rangel...

  17. Experience influences aggressive behaviour in the Argentine ant

    PubMed Central

    Van Wilgenburg, Ellen; Clémencet, Johanna; Tsutsui, Neil D.

    2010-01-01

    All animals interact with conspecifics during their life, and nearly all also display some form of aggression. An enduring challenge, however, is to understand how the experiences of an individual animal influence its later behaviours. Several studies have shown that prior winning experience increases the probability of initiating fights in later encounters. Using behavioural assays in the laboratory, we provide evidence that, in Argentine ants (Linepithema humile), the mere exposure to an opponent, without the encounter escalating to a fight, also increases the probability that it will display aggression in later encounters. Argentine ant workers differ in their propensity to attack non-colonymates, with some ants repeatedly aggressive and others consistently more docile. Although 78 per cent of the workers were consistent in their behaviour from one encounter to the next, workers that did change their behaviour after an encounter with a non-colonymate more often changed from non-aggressive to aggressive, rather than the reverse. Surprisingly, a single encounter with a non-colonymate increased a worker's propensity to fight in encounters up to a week later. An encounter with a non-colonymate also increased the probability that a worker would attack ants from a colony that it had not previously encountered. Thus, these interactions lowered the overall aggression threshold, rather than stimulating a specific aggressive response to a particular foreign colony. Finally, our data suggest that aggression towards non-colonymates increases with age. PMID:19793741

  18. Trail Pheromone Disruption of Argentine Ant Trail Formation and Foraging

    USGS Publications Warehouse

    Suckling, D.M.; Peck, R.W.; Stringer, L.D.; Snook, K.; Banko, P.C.

    2010-01-01

    Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2-3 m s-1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. ?? Springer Science+Business Media, LLC 2010.

  19. New mutualism for old: indirect disruption and direct facilitation of seed dispersal following Argentine ant invasion.

    PubMed

    Rowles, Alexei D; O'Dowd, Dennis J

    2009-01-01

    The indirect effects of biological invasions on native communities are poorly understood. Disruption of native ant communities following invasion by the Argentine ant (Linepithema humile) is widely reported to lead indirectly to the near complete collapse of seed dispersal services. In coastal scrub in southeastern Australia, we examined seed dispersal and handling of two native and two invasive alien plant species at Argentine ant-invaded or -uninvaded sites. The Argentine ant virtually eliminates the native keystone disperser Rhytidoponera victoriae, but seed dispersal did not collapse following invasion. Indeed, Argentine ants directly accounted for 92% of all ant-seed interactions and sustained overall seed dispersal rates. Nevertheless, dispersal quantity and quality among seed species differed between Argentine ant-invaded and -uninvaded sites. Argentine ants removed significantly fewer native Acacia retinodes seeds, but significantly more small seeds of invasive Polygala myrtifolia than did native ants at uninvaded sites. They also handled significantly more large seeds of A. sophorae, but rarely moved them >5 cm, instead recruiting en masse, consuming elaiosomes piecemeal and burying seeds in situ. In contrast, Argentine ants transported and interred P. myrtifolia seeds in their shallow nests. Experiments with artificial diaspores that varied in diaspore and elaiosome masses, but kept seed morphology and elaiosome quality constant, showed that removal by L. humile depended on the interaction of seed size and percentage elaiosome reward. Small diaspores were frequently taken, independent of high or low elaiosome reward, but large artificial diaspores with high reward instead elicited mass recruitment by Argentine ants and were rarely moved. Thus, Argentine ants appear to favour some diaspore types and reject others based largely on diaspore size and percentage reward. Such variability in response indirectly reduces native seed dispersal and can directly

  20. Establishment of the Geoglam Rangelands Acivity and Progress

    NASA Astrophysics Data System (ADS)

    Youngentob, K. N.; Held, A. A.; Grundy, M.; Donohue, R. J.

    2014-12-01

    With global population predicted to reach around 9 billion by 2050 and the area of arable land per person declining, there is increased focus on the need to increase food production. As part of a systematic response to that need, improved monitoring of global food production has been identified by the G20 as a priority. The Global Agricultural Monitoring initiative has been established under the Group on Earth Observations (known as GEOGLAM) as a response to this need, with initial focus on the four main food crops of the world and the major exporting regions. However, it is not only the world's croplands that will come under pressure to further increase their productivity and production. Global rangelands, scrublands and pasturelands must become more productive in producing grassland plant biomass and increased animal protein production, to supply an ever-growing global demand for essential animal protein. An essential complementary focus is needed on the sustainability of these systems to both ensure sustained productivity and to maintain the broader range of ecosystem services providing out of these large global lands. Termed "GEOGLAM Rangelands and Pasture Productivity (RAPP)", this new GEO initiative will provide the global community with the means to monitor the world's rangelands and pasture lands on a routine basis, and the capacity to produce animal protein in real-time, at global, regional and national levels. The primary scope of RAPP will be to monitor aboveground biomass and the condition of land cover for those lands and ecosystems that are integral to producing animal protein on a 'free-range', open-field basis, and their sustainable management. Using available national animal herd statistics, aims to include global and regional population information on beef cattle, goats, sheep, camels, pork, dairy cattle, wild and managed buffalo and deer. This paper will provide a broad overview of the status of implementation of the RAPP monitoring system, and

  1. Assessment of MSS spectral indexes for monitoring arid rangeland

    NASA Technical Reports Server (NTRS)

    Musick, H. B.

    1983-01-01

    The utility of MSS spectral indexes for monitoring arid rangeland vegetation was tested by determining correlations between spectral indexes and vegetation parameters and by examining retrospective MSS data to determine if vegetation change could be detected and measured using spectral indexes. MSS Band 5, albedo, and the Kauth-Thomas Brightness component appear to be useful for monitoring total vegetation cover. Multiseasonal green vegetation indexes could be used to estimate changes in the shrub/grass ratio. In retrospective monitoring, spectral index change appeared to be offset from true change, indicating that the methods used to standardize data sets for differences in solar elevation and sensor radiometric response were not completely successful.

  2. Activity of Bifenthrin, Chlorfenapyr, Fipronil, and Thiamethoxam against Argentine Ants (Hymenoptera: Formicidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bifenthrin, chlorfenapyr, fipronil, and thiamethoxam were evaluated for activity against the Argentine ant, Linepithema humile (Mayr). Mobility impairment and lethal times were determined following topical treatments. Ants were immobilized most quickly by bifenthrin, followed by chlorfenapyr and th...

  3. Fecundity and longevity of Argentine ant (Hymenoptera: Formicidae) queens in response to irradiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irradiation is a postharvest quarantine treatment option to control ants and other hitchhiker pests on fresh horticultural products traded between countries. As little is known about irradiation effects on ants, radiotolerance of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae...

  4. Rangeland degradation assessment: a new strategy based on the ecological knowledge of indigenous pastoralists

    NASA Astrophysics Data System (ADS)

    Behmanesh, Bahareh; Barani, Hossein; Abedi Sarvestani, Ahmad; Shahraki, Mohammad Reza; Sharafatmandrad, Mohsen

    2016-04-01

    In a changing world, the prevalence of land degradation is becoming a serious problem, especially in countries with arid and semi-arid rangelands. There are many techniques to assess rangeland degradation that rely on scientific knowledge but ignore indigenous people. Indigenous people have accumulated precious knowledge about land management through generations of experience. Therefore, a study was conducted to find out how indigenous people assess rangeland degradation and how their ecological knowledge can be used for rangeland degradation assessment. Interviews were conducted with the pastoralists of two sites (Dasht and Mirza Baylu), where part of both areas is located in Golestan National Park (north-eastern Iran). A structured questionnaire was designed based on 17 indicators taken from literature and also primary discussions with pastoralists in order to evaluate land degradation. A qualitative Likert five-point scale was used for scoring rangeland degradation indicators. The results revealed that pastoralists pay more attention to edaphic indicators than to vegetative and other indicators. There were significant differences between the inside and outside of the park in terms of rangeland degradation indicators for both sites. The results show that the rangelands outside of the park in both sites were degraded compared to those inside of the park, especially in the areas close to villages. It can be concluded that pastoralists have a wealth of knowledge about the vegetation and grazing animal habits that can be used in rangeland degradation assessment. It is therefore necessary to document their ecological indigenous knowledge and involve them in the process of rangeland-degradation assessment.

  5. Institutional development for sustainable rangeland resource and ecosystem management in mountainous areas of northern Nepal.

    PubMed

    Dong, Shikui; Lassoie, James; Shrestha, K K; Yan, Zhaoli; Sharma, Ekalabya; Pariya, D

    2009-02-01

    Rangelands represent one of the most important natural resources in mountainous regions of northern Nepal. However, a poor understanding of the social dimensions of rangeland use has limited their proper management and sustainable development, which represent major challenges for Nepal's resource managers. Institutional development is thought to be a viable solution to this problem and may ultimately lead to improved rangeland management in Nepal. Based on this hypothesis, a study was conduced in the Rasuwa district of northern Nepal to examine the effectiveness of institutional development at the local and national levels in mitigating the problems facing sustainable rangeland management by using an institutional analysis and development (IAD) framework. The information and data were mainly collected from different stakeholders, farmers, professionals and practitioners using a toolkit of participatory rural appraisal (PRA), workshops and literature review. It can be concluded from this case study that a number of institutional development efforts are needed to promote sustainable rangeland management in this region. First, local herders represent a repository of rich indigenous knowledge essential to sustaining sound rangeland management practices; hence, indigenous practices need to be integrated into modern technologies. Second, public services and technical support are currently unavailable or inaccessible to local herders; hence, research, development and extension interventions need to be initiated for marginalized pastoral communities. Third, rangeland institutions are incomplete and ill-organized, so institutional development of various organizations is necessary for promoting sustainable rangeland management. Fourth, the policies and governance necessary for promoting rangeland management are not well-designed; hence, governance reform and policy development need to be formulated through internal and external agencies and organizations.

  6. The GEOGLAM Rangelands and Pasture Productivity Activity: Recent Progress and Future Directions

    NASA Astrophysics Data System (ADS)

    Guerschman, J. P.; Held, A. A.; Donohue, R. J.; Renzullo, L. J.; Sims, N.; Kerblat, F.; Grundy, M.

    2015-12-01

    Rangelands and pastures cover about a third of the world's land area and support livestock production which represents ~40% of global agricultural gross domestic product. The global consumption of animal protein shows a clear increasing trend, driven by both total population and per capita income increases, putting a growing pressure on the sustainability of grazing lands worldwide. Despite their relevance, rangelands have received less attention than croplands regarding global monitoring of the resource productivity and condition. The Rangelands and Pasture Productivity (RaPP) activity is a component within the Global Agricultural Monitoring initiative established under the Group on Earth Observations (GEOGLAM) in 2013. GEOGLAM RaPP is aimed at providing the global community with the means to monitor the world's rangelands and pastures on a routine basis, and the capacity to produce animal protein in real-time, at global, regional and national levels. Since its launch two years ago GEOGLAM RAPP has made progress in the four implementation elements. These include: 1- the establishment of community of practice; 2- the development of a global monitoring system for rangeland condition; 3- the establishment of pilot sites in main rangeland systems for satellite data products validation and model testing; and 4- integration with livestock production models. Three international workshops have been held building the community of practice. A prototype monitoring system that provides global visualisations and querying capability of vegetation cover data and anomalies has been established. Pilot sites, mostly in areas with long records of field measurements of rangeland condition and productivity have been proposed for nine countries. The link to global livestock models, including physical and economic components, have been established. Future challenges for GEOGLAM RaPP have also been identified and include: better representation of the areas occupied by rangelands

  7. Argentine gas system underway for Gas del Estado

    SciTech Connect

    Bosch, H.

    1980-10-01

    Gas del Estado's giant 1074-mile Centro-Oeste pipeline project - designed to ultimately transport over 350 million CF/day of natural gas from the Neuquen basin to the Campo Duran-Buenos Aires pipeline system - is now underway. The COGASCO consortium of Dutch and Argentine companies awarded the construction project will also operate and maintain the system for 15 years after its completion. In addition to the 30-in. pipelines, the agreement calls for a major compressor station at the gas field, three intermediate compressor stations, a gas-treatment plant, liquids-recovery facilities, and the metering, control, communications, and maintenance equipment for the system. Fabricated in Holland, the internally and externally coated pipe will be double-jointed to 80-ft lengths after shipment to Argentina; welders will use conventional manual-arc techniques to weld the pipeline in the field.

  8. TGS pipeline primed for Argentine growth, CEO says

    SciTech Connect

    Share, J.

    1997-03-01

    Nowhere in Latin America has the privatization process been more aggressively pursued than in Argentina where President Carlos Menem has successfully turned over the bulk of state companies to the private sector. In the energy sector, that meant the divestiture in 1992 of Gas del Estado, the state-owned integrated gas transportation and distribution company. It was split in two transportation companies: Transportadora de Gas del Sur (TGS) and Transportadora de Gas del Norte (TGN), and eight distribution companies. TGS is the largest transporter of natural gas in Argentina, delivering more than 60 percent of that nation`s total gas consumption with a capacity of 1.9 Bcf/d. This is the second in a series of Pipeline and Gas Journal special reports that discuss the evolving strategies of the natural gas industry as it continues to restructure amid deregulation. The article focuses on TGS, the Argentine pipeline system in which Enron Corp. is a key participant.

  9. Lymphocyte subsets alteration in patients with argentine hemorrhagic fever.

    PubMed

    Vallejos, D A; Ambrosio, A M; Feuillade, M R; Maiztegui, J I

    1989-02-01

    Peripheral blood lymphocyte subpopulations were studied in 15 patients with Argentine Hemorrhagic Fever (AHF), during the acute period of the disease and in early convalescence. Anti-human Ig antibodies were used to identify B cells and monoclonal antibodies to assess T4 and T8 subsets. During the acute period of the disease, significant alterations were found in B, T4, and T8 lymphocytes (P less than .001), as well as in T4/T8 ratios (P less than .001). These abnormalities disappeared in early convalescence, around 30 days after the clinical onset. Diminished numbers of T4 lymphocytes are interpreted as relevant to the immunodepression that characterizes the acute phase of AHF.

  10. The value of milk in rangelands in Mandera County, Kenya

    NASA Astrophysics Data System (ADS)

    Ngugi, Keziah; Ertsen, Maurits

    2015-04-01

    Lack of water over expansive regions in Greater Horn of Africa created the rangelands and rangelands created pastoralism. Pastoralism involve keeping of large livestock herds and movement in search of resources, mainly water, pasture, medicine and wild foods. Several studies have been done in the last century and findings pointed at pastoralism being primitive and unsustainable. It has been predicted it would die in the last century but in the rangelands, pastoralism lives on and it is resilient. This study is based in Mandera, a pastoralism county in Kenya that neighbors Ethiopia to the North and Somalia to the East. The study sought to investigate contribution of milk to pastoralism resilience. Interviews were conducted in the field among the pastoralists, women groups, transporters, traders, government officials and consumers of milk. These information was corroborated with actual field investigations in the expansive rangelands of Mandera County. Pastoralists rarely slaughter or sell their livestock even when the animals waste away during droughts. This is because they have been through such cycles before and observed livestock make tremendous recovery when the right conditions were restored. Rangelands lack infrastructure, there are no roads, schools, telephone or hospitals. Pastoralists diet is comprised of rice, wheat and milk. It was established milk was the main source of income among pastoralists in Mandera County. From milk, the pastoralists make income that is used to purchase the other foodstuffs. Milk is available on daily basis in large quantities owing to the large number of livestock. Unfortunately, every pastoralist household produce copious amounts of milk, thus no local demand and transport infrastructure is nonexistent, making sale of milk a near impossible task. The findings showed the pastoralists have established unique routes through which milk reach the markets in urban centers where demand is high. Urbanization sustain pastoralism. These

  11. Soils of the Galindez Island, Argentine archipelago, Western Antarctica

    NASA Astrophysics Data System (ADS)

    Abakumov, Evgeny; Parnikoza, Ivan

    2015-04-01

    Antarctic Peninsula is a part of Antarctica which is characterized by increased soil diversity, caused by specific of parent materials and diversity of non-vascular and vascular plants. Soils of Galindez Island have been investigated during the 18-th Ukranian Antarctic Expedition 2013/14. This Island situated in Argentine archipelago (coastal part of Antarctic Peninsula). Soils of Galindez Island presented by following types: Leptosols, Lithosols, Histic Lithosols and Leptosols and some Gleyic soils, located in lowlands and coastal parts. An average solum profile thickness is 3-19 cm which result from the small depth of debris's, underplayed by massive crystallic rocks. The permafrost layer is located within the massive rock, but not in coarse friable parent material. The soils with bird influence are widely spread both in coastal and central part of Island. In the coastal parts we can find typical Ornithosols in the penguin rockeries areas. The main aim of our investigation was characterization of soils formed under vegetation, exactly under Deschampsia antarctica Desv. localities. Argentine Islands is the central part of D. antarctica spreading area in region of Antarctic peninsula. Probably, these islands colonized by hairgrass mainly due to ornitogenic activity. So, coastal population appearance related with Larus dominicanus nest areas and feeding activity. Thus, we found typical post ornithogenic soils here. This kind of soils we also observed in population of hairgrass of Galindez mainland where it was connected with the other Antarctic bird - Catharacta maccormicki activity. Thus, the soil diversity and soil geochemistry of the Galindez Island are closely related to the activity of birds. The spatial pattern of soils, their chemistry and organic matter quality is discussed in relation with distribution of bird nesting and feeding activity.

  12. Comparison of LANDSAT-2 and field spectrometer reflectance signatures of south Texas rangeland plant communities

    NASA Technical Reports Server (NTRS)

    Richardson, A. J.; Escobar, D. E.; Gausman, H. W.; Everitt, J. H. (Principal Investigator)

    1982-01-01

    The accuracy was assessed for an atmospheric correction method that depends on clear water bodies to infer solar and atmospheric parameters for radiative transfer equations by measuring the reflectance signature of four prominent south Texas rangeland plants with the LANDSAT satellite multispectral scanner (MSS) and a ground based spectroradiometer. The rangeland plant reflectances produced by the two sensors were correlated with no significant deviation of the slope from unity or of the intercept from zero. These results indicated that the atmospheric correction produced LANDSAT MSS estimates of rangeland plant reflectances that are as accurate as the ground based spectroradiometer.

  13. Multiscale sagebrush rangeland habitat modeling in southwest Wyoming

    USGS Publications Warehouse

    Homer, Collin G.; Aldridge, Cameron L.; Meyer, Debra K.; Coan, Michael J.; Bowen, Zachary H.

    2009-01-01

    Sagebrush-steppe ecosystems in North America have experienced dramatic elimination and degradation since European settlement. As a result, sagebrush-steppe dependent species have experienced drastic range contractions and population declines. Coordinated ecosystem-wide research, integrated with monitoring and management activities, would improve the ability to maintain existing sagebrush habitats. However, current data only identify resource availability locally, with rigorous spatial tools and models that accurately model and map sagebrush habitats over large areas still unavailable. Here we report on an effort to produce a rigorous large-area sagebrush-habitat classification and inventory with statistically validated products and estimates of precision in the State of Wyoming. This research employs a combination of significant new tools, including (1) modeling sagebrush rangeland as a series of independent continuous field components that can be combined and customized by any user at multiple spatial scales; (2) collecting ground-measured plot data on 2.4-meter imagery in the same season the satellite imagery is acquired; (3) effective modeling of ground-measured data on 2.4-meter imagery to maximize subsequent extrapolation; (4) acquiring multiple seasons (spring, summer, and fall) of an additional two spatial scales of imagery (30 meter and 56 meter) for optimal large-area modeling; (5) using regression tree classification technology that optimizes data mining of multiple image dates, ratios, and bands with ancillary data to extrapolate ground training data to coarser resolution sensors; and (6) employing rigorous accuracy assessment of model predictions to enable users to understand the inherent uncertainties. First-phase results modeled eight rangeland components (four primary targets and four secondary targets) as continuous field predictions. The primary targets included percent bare ground, percent herbaceousness, percent shrub, and percent litter. The

  14. Collaborative adaptive landscape management (CALM) in rangelands: Discussion of general principles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The management of rangeland landscapes involves broad spatial extents, mixed land ownership, and multiple resource objectives. Management outcomes depend on biophysical heterogeneity, highly variable weather conditions, land use legacies, and spatial processes such as wildlife movement, hydrological...

  15. Overgrazing- How far are we from passing the tipping point of turning our rangelands into desert?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ecological science, particularly with regard to Mongolian rangelands, is not able to estimate when a tipping point will be passed. Nonetheless, it does provide a framework for responding to the threat of desertification tipping points. ...

  16. Evaluation of fine fescue grasses identifies resources for improved ecological function under rangeland stress environments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fine-leaved fescue (Festuca ssp.) grasses have potential for contributing to increased rangeland productivity given their comparatively high drought and heat tolerance. Therefore, plant performance trials were developed to evaluate geographically diverse fine fescue materials for their application ...

  17. SOIL MICROARTHROPODS AS INDICATORS OF EXPOSURE TO ENVIRONMENTAL STRESS IN CHIHUAHUAN DESERT RANGELANDS

    EPA Science Inventory

    We studied soil microarthropod communities along livestock grazing disturbance gradients, inside and outside grazing exclosures, and on areas subjected to restoration efforts (herbicide and bulldozing) in order to test the suitability of mites as indicators of rangeland soil qual...

  18. Success of seeding native compared with introduced perennial vegetation for revegetating medusahead-invaded sagebrush rangeland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Millions of hectares of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle &Young) rangeland have been invaded by medusahead (Taeniatherum caput-medusae [L.] Nevski), an exotic annual grass that degrades wildlife habitat, reduces forage production, and decreases biodiversity....

  19. Potential for Carbon Sequestration using Organic Amendments on Rangeland Soils

    NASA Astrophysics Data System (ADS)

    Ryals, R.; Silver, W. L.

    2009-12-01

    Managed rangelands represent a geographically large land-use footprint and thus have considerable potential to sequester carbon (C) in soil through changes in management practices. Organic amendments are frequently added to agricultural and rangeland soils in an effort to improve fertility and yield, yet little is known about their impact on greenhouse gas dynamics and soil biogeochemical dynamics, especially in rangeland soils. This research aims to explore the effects of organic amendments on soil chemical and physical properties, plant inputs, and soil C and N dynamics in managed rangeland ecosystems. Our research uses field manipulations at two Mediterranean grassland ecosystems replicated within and across bioclimatic zones: the Sierra Foothills Research and Extension Center (SFREC) in Browns Valley, CA and the Nicasio Native Grass Ranch in Nicasio, CA. Both sites are dominated by annual grasses and are moderately grazed by cattle. Three replicate blocks at each site contain 60m x 25m treatment plots (organic amendments and control) with 5m buffer strips. Organic amendments were applied at a level of 14 MgC/ha (equivalent to a 1.27cm surface dressing) at the beginning of the wet season (December 2008). During the wet season (October through June), carbon dioxide (CO2) flux was measured weekly using a LI-8100, while fluxes of methane (CH4) and nitrous oxide (N2O) were measured biweekly using static flux chambers. During the dry season (June through September), fluxes were measured biweekly and monthly, respectively. Soil organic C (SOC) and nitrogen (N) were measured prior to treatment and seven months following treatment at 0-10, 10-30, 30-50, and 50-100 cm depths. Soil moisture and temperature were measured continuously. Changes in oxidative and hydrolytic extracellular enzyme activities are also being explored. After the first year of management, both sites responded similarly to treatments in both trend and magnitude. For example, at SFREC, total soil

  20. Soil degradation in wooded rangelands of southwest Spain

    NASA Astrophysics Data System (ADS)

    Schnabel, S.; Lavado Contador, J. F.; Gómez Gutiérrez, Á.

    2009-04-01

    The paper presents a review on soil degradation studies carried out since 1990 in wooded rangelands in Extremadura. In the semiarid and subhumid parts of the south-western Iberian Peninsula open evergreen woodlands dominated by Quercus species are widespread (dehesas and montados). They are composed of grasslands with a varying degree of tree cover, ranging from treeless to more than 80 individuals per hectare. In some areas shrubs form a third component of the vegetation. Dehesas are subject to a complex exploitation system with agro-silvo-pastoral land use. The dominant soil degradation phenomena include different forms of water erosion and physical and biological degradation. Regarding soil erosion and surface hydrology, research has been carried out at different spatial scales. Sheetwash and overland flow were investigated along hillslopes and in microplots, whereas gully erosion and runoff production were monitored in small experimental catchments. Recently, physical and biological degradation has been studied in a large number of farms, representing the most important types of rangelands in the region of Extremadura. This included a rapid appraisal of degradation features, the determination of soil properties and a study on the distribution and activity of gullies. Soil degradation varies strongly with regard to the natural factors, but also with respect to land use and management. Sheetwash (interrill erosion) is the dominant process on hillslopes, with a mean soil loss rate of 0.63 t ha-1. However rainfall variation and land management, especially livestock density, produce changes in soil cover. With low to moderate livestock densities and during prolonged periods with low rainfall (droughts), the vegetation cover may be strongly reduced, provoking high soil losses, whereas during normal or humid periods interrill erosion is low. Excessive stocking rates may exacerbate sheetwash, producing severe soil degradation, regardless of rainfall conditions. In

  1. A simple graphical approach to quantitative monitoring of rangelands

    USGS Publications Warehouse

    Riginos, C.; Herrick, J.E.; Sundaresan, S.R.; Farley, C.; Belnap, J.

    2011-01-01

    The article reviews graphical interpretation of the four monitoring methods that can be used to generate a variety of indicators of rangeland ecosystem function. Data for all four of the monitoring methods can be recorded on a single data sheet that is designed to be usable by somebody with minimal literacy. Indicators of plant and ground cover are central to most long-term monitoring systems. Plant and ground-cover data inform managers about forage availability, plant community composition and structure, and risk of runoff and erosion. The spatial arrangement of plants at a site in addition to the percent of the ground that is covered by plants is an important determinant of erosion potential. Vertical vegetation structure can be monitored by capturing data on maximum plant height at each stick location. Plant density method can provide an early indicator of future changes in plant cover, forage, quality, and habitat structure.

  2. Capability of AVHRR data in discriminating rangeland cover mixtures

    USGS Publications Warehouse

    Senay, Gabriel B.; Elliott, R.L.

    2002-01-01

    A combination of high temporal resolution Advanced Very High Resolution Radiometer (AVHRR) data and high spatial information Map Information Analysis and Display System (MIADS) landuse/landcover data from the United States Department of Agriculture-Natural Resources Conservation Service (USDA-NRCS) were used to investigate the feasibility of using the combined dataset for regional evapotranspiration (ET) studies. It was shown that the biweekly maximum Normalized Difference Vegetation Index (NDVI) composite AVHRR data were capable of discriminating rangelands with different types of trees and shrubs species. AVHRR data also showed a potential to distinguish canopy cover differences within a mix of similar species. The combination of MIADS data and AVHRR data can be used to study temporal dynamics of various cover types for use in regional ET estimates.

  3. Personality in recovered depressed elderly.

    PubMed

    Schneider, L S; Zemansky, M F; Bender, M; Sloane, R B

    1992-01-01

    Personality traits in euthymic elderly subjects with and without past histories of major depressive episodes were assessed using the Structured Clinical Interview for DSM-III-R and the Social Adjustment Scale-SR. Recovered depressed subjects were characterized by significantly more personality traits from DSM-III-R Clusters B and C than controls, and they exhibited differences in social adjustment, as well. Subjects who have recovered from depressive episodes may show significant differences in personality and social adjustment that might represent residua of past depression, a trait characteristic, or a risk factor for recurrence.

  4. Nitrate and sediment fluxes from a California rangeland watershed.

    PubMed

    Lewis, David J; Singer, Michael J; Dahlgren, Randy A; Tate, Kenneth W

    2006-01-01

    Long-term water quality records for assessing natural variability, impact of management, and that guide regulatory processes to safeguard water resources are rare for California oak woodland rangelands. This study presents a 20-yr record (1981-2000) of nitrate-nitrogen (NO(3)-N) and suspended sediment export from a typical, grazed oak woodland watershed (103 ha) in the northern Sierra Nevada foothills of California. Mean annual precipitation over the 20-yr period was 734 mm yr(-1) (range 366-1205 mm yr(-1)). Mean annual stream flow was 353 mm y(-1) (range 87-848 mm yr(-1)). Average annual stream flow was 48.1 +/- 16% of precipitation. Mean annual NO(3)-N export was 1.6 kg ha(-1) yr(-1) (range 0.18-3.6 kg ha(-1) yr(-1)). Annual NO(3)-N export significantly (P < 0.05) increased with increasing annual stream flow and precipitation. Mean daily NO(3)-N export was 0.004 kg ha(-1) d(-1) (range 10(-5) to 0.55 kg ha(-1) d(-1)). Mean annual suspended sediment export was 198 kg ha(-1) yr(-1) (range 23-479 kg ha(-1) yr(-1)). There was a positive relationship (P < 0.05) between annual suspended sediment export, annual stream flow and precipitation. Mean daily suspended sediment export was 0.54 kg ha(-1) d(-1) (range 10(-4) to 155 kg ha(-1) d(-1)). Virtually no sediment was exported during the dry season. The large variation in daily and annual fluxes highlights the necessity of using long-term records to establish quantitative water quality targets for rangelands and demonstrates the difficulty of designing a water quality monitoring program for these ecosystems.

  5. Evaluation of Bare Ground on Rangelands using Unmanned Aerial Vehicles

    SciTech Connect

    Robert P. Breckenridge; Maxine Dakins

    2011-01-01

    Attention is currently being given to methods that assess the ecological condition of rangelands throughout the United States. There are a number of different indicators that assess ecological condition of rangelands. Bare Ground is being considered by a number of agencies and resource specialists as a lead indicator that can be evaluated over a broad area. Traditional methods of measuring bare ground rely on field technicians collecting data along a line transect or from a plot. Unmanned aerial vehicles (UAVs) provide an alternative to collecting field data, can monitor a large area in a relative short period of time, and in many cases can enhance safety and time required to collect data. In this study, both fixed wing and helicopter UAVs were used to measure bare ground in a sagebrush steppe ecosystem. The data were collected with digital imagery and read using the image analysis software SamplePoint. The approach was tested over seven different plots and compared against traditional field methods to evaluate accuracy for assessing bare ground. The field plots were located on the Idaho National Laboratory (INL) site west of Idaho Falls, Idaho in locations where there is very little disturbance by humans and the area is grazed only by wildlife. The comparison of fixed-wing and helicopter UAV technology against field estimates shows good agreement for the measurement of bare ground. This study shows that if a high degree of detail and data accuracy is desired, then a helicopter UAV may be a good platform. If the data collection objective is to assess broad-scale landscape level changes, then the collection of imagery with a fixed-wing system is probably more appropriate.

  6. Recovering Zinc From Discarded Tires

    NASA Technical Reports Server (NTRS)

    Du Fresne, E. R.

    1984-01-01

    Zinc sulfate monohydrate sold at profit. Shredded tire material steeped in three sulfuric acid baths to extract zinc. Final product removed by evaporating part of solution until product crystallizes out. Recovered as zinc sulfate monohydrate and sold as fertilizer or for general use.

  7. PROCESS OF RECOVERING ALKALI METALS

    DOEpatents

    Wolkoff, J.

    1961-08-15

    A process is described of recovering alkali metal vapor by sorption on activated alumina, activated carbon, dehydrated zeolite, activated magnesia, or Fuller's earth preheated above the vaporization temperature of the alkali metal and subsequent desorption by heating the solvent under vacuum. (AEC)

  8. Prescribed Fire Effects on Runoff, Erosion, and Soil Water Repellency on Steeply-Sloped Sagebrush Rangeland over a Five Year Period

    NASA Astrophysics Data System (ADS)

    Williams, C. J.; Pierson, F. B.; Al-Hamdan, O. Z.

    2014-12-01

    Fire is an inherent component of sagebrush steppe rangelands in western North America and can dramatically affect runoff and erosion processes. Post-fire flooding and erosion events pose substantial threats to proximal resources, property, and human life. Yet, prescribed fire can serve as a tool to manage vegetation and fuels on sagebrush rangelands and to reduce the potential for large catastrophic fires and mass erosion events. The impact of burning on event hydrologic and erosion responses is strongly related to the degree to which burning alters vegetation, ground cover, and surface soils and the intensity and duration of precipitation. Fire impacts on hydrologic and erosion response may be intensified or reduced by inherent site characteristics such as topography and soil properties. Parameterization of these diverse conditions in predictive tools is often limited by a lack of data and/or understanding for the domain of interest. Furthermore, hydrologic and erosion functioning change as vegetation and ground cover recover in the years following burning and few studies track these changes over time. In this study, we evaluated the impacts of prescribed fire on vegetation, ground cover, soil water repellency, and hydrologic and erosion responses 1, 2, and 5 yr following burning of a mountain big sagebrush community on steep hillslopes with fine-textured soils. The study site is within the Reynolds Creek Experimental Watershed, southwestern Idaho, USA. Vegetation, ground cover, and soil properties were measured over plot scales of 0.5 m2 to 9 m2. Rainfall simulations (0.5 m2) were used to assess the impacts of fire on soil water repellency, infiltration, runoff generation, and splash-sheet erosion. Overland flow experiments (9 m2) were used to assess the effects of fire-reduced ground cover on concentrated-flow runoff and erosion processes. The study results provide insight regarding fire impacts on runoff, erosion, and soil water repellency in the immediate and

  9. First report of viral infections that affect argentine honeybees.

    PubMed

    Reynaldi, Francisco José; Sguazza, Guillermo Hernán; Pecoraro, Marcelo Ricardo; Tizzano, Marco Andrés; Galosi, Cecilia Mónica

    2010-12-01

    Honey is one of the most important agricultural products for export in Argentina. In fact, more than 3.5 million beehives and 50 000 beekeepers are related with this production, mainly located in Buenos Aires province. Honeybee mortality is a serious problem that beekeepers in Argentina have had to face during the last 3 years. It is known that the consequence of the complex interactions between environmental and beekeeping parameters added to the effect of different disease agents such as viruses, bacteria, fungi and parasitic mites may result in a sudden collapse of the colony. In addition, multiple viral infections are frequently detected concomitantly in bee colonies. We describe here the preliminary results of a survey of three honeybee-pathogenic viruses, acute bee paralysis viruses (ABPV), chronic bee paralysis viruses (CBPV) and Sacbrood viruses (SBV) detected during a screening of 61 apiaries located in the main honey producer province using a RT-PCR assay. This is the first molecular report of the presence of these viruses in Argentine apiaries.

  10. Feeding strategy and cannibalism of the Argentine hake Merluccius hubbsi.

    PubMed

    Ocampo Reinaldo, M; González, R; Romero, M A

    2011-12-01

    The diet composition and feeding strategy of the Argentine hake Merluccius hubbsi in the San Matías Gulf were analysed in order to use this information for the sustainable management of the fishery. Merluccius hubbsi behaved as an opportunistic predator. Small M. hubbsi consumed planktonic crustaceans, whereas medium and large fish ate numerous prey taxa with low frequency of occurrence and variable specific abundance. Intra- and intercohort cannibalism were detected in all size groups and were particularly significant in large M. hubbsi. Medium-sized M. hubbsi consumed small conspecifics and large-sized M. hubbsi consumed both small and medium M. hubbsi. These results indicate that the removal of large M. hubbsi by fishing may increase the risk of overfishing by two combined effects: a direct effect of recruitment-overfishing and an indirect effect of growth-overfishing through an enhanced cannibalism of medium M. hubbsi on small M. hubbsi. Intra- and intercohort cannibalism and other trophic relationships in the M. hubbsi should therefore be considered explicitly in stock assessment models.

  11. Clinical and epidemiological patterns of Argentine haemorrhagic fever

    PubMed Central

    Maiztegui, J. I.

    1975-01-01

    The epidemiology of Argentine haemorrhagic fever (AHF) is closely related to cricetine rodents acting as natural hosts of Junin virus. The endemo-epidemic area, which has increased 5 times since the disease was first recognized 15-20 years ago, is located in a densely populated region of Argentina. It has been shown that the virus of LCM is active in humans and rodents of the AHF endemic area; this demonstrates the simultaneous presence of two arenaviruses pathogenic for man in a given geographic location. The disease is characterized by haematological, renal, neurological and cardiovascular changes. Electron microscopy and immunohistochemical studies have shown cytopathic changes, characteristic intracellular virus-like particles, and antigenic determinants of Junin virus in different organs from 9 cases of AHF. No deposits of immunoglobulins or C3 were found in the kidneys; in addition, an absence of fibrinogen and C3 in the hepatocytes and of immunoglobulins in the spleen was observed. These findings suggest a direct viral pathogenic action in the human disease. Ultrastructural and immunofluorescence studies in tissues of guinea-pigs inoculated with two strains of Junin virus revealed the presence of the same types of virus-like particles and antigenic determinants of Junin virus as were encountered in the human subjects with AHF. ImagesFig. 2Fig. 3 PMID:1085212

  12. The tropopause at southern extratropical latitudes: Argentine operational rawinsonde climatology

    NASA Astrophysics Data System (ADS)

    Bischoff, Susana A.; Canziani, Pablo O.; Yuchechen, Adrián E.

    2007-02-01

    Argentine operational rawinsonde records spanning a 30-year period (1968-1997) were used to study the climatology of the tropopause from the subtropics to the southern mid-latitudes, approximately along the 60°W meridian. The thermal tropopause annual cycle as well as its variability was analyzed at three sites: Resistencia (RES), Ezeiza (EZE), and Comodoro Rivadavia (CRD). Single and double tropopause observations were studied, given the comparatively frequent occurrence of double tropopause events at all three sites. The tropopause behavior at RES and CRD is distinct, whereas at EZE it shows a winter evolution similar to the one at CRD and a summer evolution closer to the one at RES, in agreement with the annual evolution of the subtropical jet. The tropopause evolution is discussed under the light of the dynamic climatology of southern South America. In the presence of double tropopause events and in terms of potential temperature, it should be noted that the upper tropopause temperature is close to the 380 K isentropic, i.e. the tropical tropopause layer. Moreover, the lower tropopause and single tropopause events are fairly close together, i.e. coincident with the lowermost stratosphere. Considering previous research and results from the present analysis, a definition of Extratropical Tropopause Layer (ExTL) is introduced in this work. It is proposed that the lowermost stratosphere should be regarded as the ExTL.

  13. [Distribution of Lutzomyia longipalpis in the Argentine Mesopotamia, 2010].

    PubMed

    Salomon, Oscar D; Fernandez, Maria S; Santini, María S; Saavedra, Silvina; Montiel, Natalia; Ramos, Marina A; Rosa, Juan R; Szelag, Enrique A; Martinez, Mariela F

    2011-01-01

    The first case of visceral leishmaniasis (VL) in Argentina was reported in 2006 in Posadas, Misiones. During the summer 2008-2009 Lutzomyia longipalpis, the VL vector, and canine VL cases were already spread along the province of Corrientes. In order to know the distribution of VL risk, systematic captures of the vector were performed between February and March 2010, in 18 areas of the provinces of Entre Ríos and Corrientes, and the city of Puerto Iguazú, Misiones, with a total of 313 traps/night. We confirmed the presence of Lu. longipalpis, for the first time in Chajarí (Entre Ríos), Alvear, La Cruz, Curuzú Cuatiá and Bella Vista (Corrientes), and Puerto Iguazú (Misiones). In Santo Tome and Monte Caseros (Corrientes), where the vector had been previously reported, traps with more samples were obtained with 830 and 126 Lu. Longipalpis trap/site/night respectively. These results show that the vector of urban VL continues spreading in the Argentine territory. Simultaneously, the spread of the parasite and the resulting human VL cases are associated with the dispersion of reservoirs, infected dogs, with or without clinical symptoms or signs, due to human transit.

  14. Recovering entanglement by local operations

    SciTech Connect

    D’Arrigo, A.; Lo Franco, R.; Benenti, G.; Paladino, E.; Falci, G.

    2014-11-15

    We investigate the phenomenon of bipartite entanglement revivals under purely local operations in systems subject to local and independent classical noise sources. We explain this apparent paradox in the physical ensemble description of the system state by introducing the concept of “hidden” entanglement, which indicates the amount of entanglement that cannot be exploited due to the lack of classical information on the system. For this reason this part of entanglement can be recovered without the action of non-local operations or back-transfer process. For two noninteracting qubits under a low-frequency stochastic noise, we show that entanglement can be recovered by local pulses only. We also discuss how hidden entanglement may provide new insights about entanglement revivals in non-Markovian dynamics.

  15. Introduced and invasive species in novel rangeland ecosystems: friends or foes?

    USGS Publications Warehouse

    Belnap, Jayne; Ludwig, John A.; Wilcox, Bradford P.; Betancourt, Julio L.; Dean, W. Richard J.; Hoffmann, Benjamin D.; Milton, Sue J.

    2012-01-01

    Globally, new combinations of introduced and native plant and animal species have changed rangelands into novel ecosystems. Whereas many rangeland stakeholders (people who use or have an interest in rangelands) view intentional species introductions to improve forage and control erosion as beneficial, others focus on unintended costs, such as increased fire risk, loss of rangeland biodiversity, and threats to conservation efforts, specifically in nature reserves and parks. These conflicting views challenge all rangeland stakeholders, especially those making decisions on how best to manage novel ecosystems. To formulate a conceptual framework for decision making, we examined a wide range of novel ecosystems, created by intentional and unintentional introductions of nonnative species and land-use–facilitated spread of native ones. This framework simply divides decision making into two types: 1) straightforward–certain, and 2) complex–uncertain. We argue that management decisions to retain novel ecosystems are certain when goods and services provided by the system far outweigh the costs of restoration, for example in the case of intensively managed Cenchrus pastures. Decisions to return novel ecosystems to natural systems are also certain when the value of the system is low and restoration is easy and inexpensive as in the case of biocontrol of Opuntia infestations. In contrast, decisions whether to retain or restore novel ecosystems become complex and uncertain in cases where benefits are low and costs of control are high as, for example, in the case of stopping the expansion of Prosopis and Juniperus into semiarid rangelands. Decisions to retain or restore novel ecosystems are also complex and uncertain when, for example, nonnative Eucalyptus trees expand along natural streams, negatively affecting biodiversity, but also providing timber and honey. When decision making is complex and uncertain, we suggest that rangeland managers utilize cost–benefit analyses

  16. Perceptions of Ranchers About Medusahead ( Taeniatherum caput-medusae (L.) Nevski) Management on Sagebrush Steppe Rangelands

    NASA Astrophysics Data System (ADS)

    Johnson, Dustin D.; Davies, Kirk W.; Schreder, Peter T.; Chamberlain, Anna-Marie

    2011-09-01

    Medusahead ( Taeniatherum caput-medusae (L.) Nevski) is an exotic annual grass invading rangelands in the western United States. Medusahead is a serious management concern because it decreases biodiversity, reduces livestock forage production, and degrades the ecological function of rangelands. Despite the obvious importance of ranchers as partners in preventing and managing medusahead in rangelands, little is known about their perceptions and behaviors concerning medusahead management. We present the results of a survey of ranchers operating on sagebrush steppe rangeland in a three-county area in southeast Oregon encompassing over 7.2 million ha. The primary objective of this research was to determine if the presence of medusahead on a ranch influenced its operator's perceptions and behaviors concerning invasive plant control and prevention. Ranchers operating on medusahead-infested rangeland were more likely to indicate increased awareness and concern about medusahead and the potential for its continued expansion. Ranchers operating on rangeland invaded by medusahead were also more likely to indicate use of measures to prevent the spread of medusahead and other invasive plants on rangeland, interest in educational opportunities concerning invasive annual grass management, and plans for controlling invasive annual grasses in the future. This study revealed an alarming trend in which individuals are less likely to implement important prevention measures and participate in education opportunities to improve their knowledge of invasive plants until they directly experience the negative consequences of invasion. Information campaigns on invasive plants and their impacts may rectify this problem; however, appropriate delivery methods are critical for success. Web- or computer-based invasive plant information and tools were largely unpopular among ranchers, whereas traditional forms of information delivery including brochures/pamphlets and face-to-face interaction were

  17. Methods of recovering alkali metals

    DOEpatents

    Krumhansl, James L; Rigali, Mark J

    2014-03-04

    Approaches for alkali metal extraction, sequestration and recovery are described. For example, a method of recovering alkali metals includes providing a CST or CST-like (e.g., small pore zeolite) material. The alkali metal species is scavenged from the liquid mixture by the CST or CST-like material. The alkali metal species is extracted from the CST or CST-like material.

  18. Transitions in rangeland evaluations: A review of the major transitions in rangeland evaluations during the last 25 years and speculation about future evaluations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    New technologies in remote sensing allow us to view land changes over much larger areas than in the past. Our increased understanding of the importance of linkages among the living components (all of the interacting organisms) and non-living components (e.g., soils, air, and water) of rangelands and...

  19. Biotic and abiotic controls of argentine ant invasion success at local and landscape scales

    USGS Publications Warehouse

    Menke, S.B.; Fisher, R.N.; Jetz, W.; Holway, D.A.

    2007-01-01

    Although the ecological success of introduced species hinges on biotic interactions and physical conditions, few experimental studies - especially on animals - have simultaneously investigated the relative importance of both types of factors. The lack of such research may stem from the common assumption that native and introduced species exhibit similar environmental tolerances. Here we combine experimental and spatial modeling approaches (1) to determine the relative importance of biotic and abiotic controls of Argentine ant (Linepithema humile) invasion success, (2) to examine how the importance of these factors changes with spatial scale in southern California (USA), and (3) to assess how Argentine ants differ from native ants in their environmental tolerances. A factorial field experiment that combined native ant removal with irrigation revealed that Argentine ants failed to invade any dry plots (even those lacking native ants) but readily invaded all moist plots. Native ants slowed the spread of Argentine ants into irrigated plots but did not prevent invasion. In areas without Argentine ants, native ant species showed variable responses to irrigation. At the landscape scale, Argentine ant occurrence was positively correlated with minimum winter temperature (but not precipitation), whereas native ant diversity increased with precipitation and was negatively correlated with minimum winter temperature. These results are of interest for several reasons. First, they demonstrate that fine-scale differences in the physical environment can eclipse biotic resistance from native competitors in determining community susceptibility to invasion. Second, our results illustrate surprising complexities with respect to how the abiotic factors limiting invasion can change with spatial scale, and third, how native and invasive species can differ in their responses to the physical environment. Idiosyncratic and scale-dependent processes complicate attempts to forecast where

  20. A mutualism with a native membracid facilitates pollinator displacement by Argentine ants.

    PubMed

    Lach, Lori

    2007-08-01

    The loss of biodiversity and associated ecosystem services are major threats posed by the spread of alien invasive species. Invasive ants are frequently associated with declines in the diversity of ground-dwelling arthropods but also may affect plants through their attraction to floral nectar and tending of hemipterans. Protea nitida is a tree native to the South African fynbos that hosts a native membracid, Beaufortiana sp., which is tended by ants. Here I compare Argentine ants (Linepithema humile) to native ants in their attraction to P. nitida inflorescences in the presence and absence of the membracid, and their effects on other floral arthropod visitors, seed set, and ovule predation. Argentine ant discovery of inflorescences increased at least 13-fold when membracids were present on the branch, whereas native ant discovery of inflorescences was only doubled by membracid presence at one site in one study year and was unaffected in the other three site-years. Excluding Argentine ants from inflorescences resulted in an increase in several arthropod taxa and potential pollinators; native ant exclusion had no positive effects. Thus the mutualism between Argentine ants and the membracid is facilitating pollinator deterrence by the ants. Though Argentine ants were not associated with a decline in P. nitida seed set or ovule predation, declines in generalist insect pollinators may have ramifications for the 83% of fynbos plants that are insect pollinated. Pitfall traps showed that Argentine ants were not more abundant than native ants in non-invaded sites. Focusing only on abundance on the ground and displacement of ground-dwelling arthropod fauna may lead to an underestimate of the effects of invasive ants on their adopted communities.

  1. Comparison of rangeland vegetation sampling techniques in the Central Grasslands

    USGS Publications Warehouse

    Stohlgren, T.J.; Bull, K.A.; Otsuki, Y.

    1998-01-01

    Maintaining native plant diversity, detecting exotic species, and monitoring rare species are becoming important objectives in rangeland conservation. Four rangeland vegetation sampling techniques were compared to see how well they captured local pant diversity. The methods tested included the commonly used Parker transects, Daubenmire transects as modified by the USDA Forest Service, a new transect and 'large quadrat' design proposed by the USDA Agricultural Research Service, and the Modified-Whittaker multi-scale vegetation plot. The 4 methods were superimposed in shortgrass steppe, mixed grass prairie, northern mixed prairie, and tallgrass prairie in the Central Grasslands of the United States with 4 replicates in each prairie type. Analysis of variance tests showed significant method effects and prairie type effects, but no significant method X type interactions for total species richness, the number of native species, the number of species with less than 1 % cover, and the time required for sampling. The methods behaved similarly in each prairie type under a wide variety of grazing regimens. The Parker, large quadrat, and Daubenmire transects significantly underestimated the total species richness and the number of native species in each prairie type, and the number of species with less than 1 % cover in all but the tallgrass prairie type. The transect techniques also consistently missed half the exotic species, including noxious weeds, in each prairie type. The Modified-Whittaker method, which included an exhaustive search for plant species in a 20 x 50 m plot, served as the baseline for species richeness comparisons. For all prairie types, the Modified-Whittaker plot captured an average of 42. (?? 2.4; 1 S.E.) plant species per site compared to 15.9 (?? 1.3), 18.9 (?? 1.2), and 22.8 (?? 1.6) plant species per site using the Parker, large quadrat, and Daubenmire transect methods, respectively. The 4 methods captured most of the dominant species at each site

  2. Agronomic characterization of the Argentina Indicator Region. [U.S. corn belt and Argentine pampas

    NASA Technical Reports Server (NTRS)

    Hicks, D. R. (Principal Investigator)

    1982-01-01

    An overview of the Argentina indicator region including information on topography, climate, soils and vegetation is presented followed by a regionalization of crop livestock land use. Corn/soybean production and exports as well as agricultural practices are discussed. Similarities and differences in the physical agronomic scene, crop livestock land use and agricultural practices between the U.S. corn belt and the Argentine pampa are considered. The Argentine agricultural economy is described. Crop calendars for the Argentina indicator region, an accompanying description, notes on crop-livestock zones, wheat production, field size, and agricultural problems and practices are included.

  3. Incorporating grazing into an eco-hydrologic model: Simulating coupled human and natural systems in rangelands

    NASA Astrophysics Data System (ADS)

    Reyes, J. J.; Liu, M.; Tague, C.; Choate, J. S.; Evans, R. D.; Johnson, K. A.; Adam, J. C.

    2013-12-01

    Rangelands provide an opportunity to investigate the coupled feedbacks between human activities and natural ecosystems. These areas comprise at least one-third of the Earth's surface and provide ecological support for birds, insects, wildlife and agricultural animals including grazing lands for livestock. Capturing the interactions among water, carbon, and nitrogen cycles within the context of regional scale patterns of climate and management is important to understand interactions, responses, and feedbacks between rangeland systems and humans, as well as provide relevant information to stakeholders and policymakers. The overarching objective of this research is to understand the full consequences, intended and unintended, of human activities and climate over time in rangelands by incorporating dynamics related to rangeland management into an eco-hydrologic model that also incorporates biogeochemical and soil processes. Here we evaluate our model over ungrazed and grazed sites for different rangeland ecosystems. The Regional Hydro-ecologic Simulation System (RHESSys) is a process-based, watershed-scale model that couples water with carbon and nitrogen cycles. Climate, soil, vegetation, and management effects within the watershed are represented in a nested landscape hierarchy to account for heterogeneity and the lateral movement of water and nutrients. We incorporated a daily time-series of plant biomass loss from rangeland to represent grazing. The TRY Plant Trait Database was used to parameterize genera of shrubs and grasses in different rangeland types, such as tallgrass prairie, Intermountain West cold desert, and shortgrass steppe. In addition, other model parameters captured the reallocation of carbon and nutrients after grass defoliation. Initial simulations were conducted at the Curlew Valley site in northern Utah, a former International Geosphere-Biosphere Programme Desert Biome site. We found that grasses were most sensitive to model parameters affecting

  4. [Evaluation and treatment of interstitial lung disease in Argentine].

    PubMed

    Mosca, C; Quadrelli, S; Castro Zorrilla, L; Castagnino, J

    2000-01-01

    To determine the availability and usual management of interstitial lung diseases (ILD) in our country, the Section of Interstitial Lung Diseases of the Argentine Association for Respiratory Medicine (AAMR) made a survey about diagnostic methodology and treatment of ILD. A total of 115 answers were obtained (38.5%), 43% of them among physicians living in the provinces. Availability of diffusing capacity of the lung for carbon monoxide test (DLCO) is limited: 25.4% never have access to it and 35.6% can seldom use it. Availability to thoracic CT scan is wider: 85% may use if often (32.4%) or always (52.6%). Bronchoscopy is commonly available in 87.7% of the physicians either often (21.9%) or always (65.8%). However, only 20.2% perform BAL and 13.1% transbronchial biopsy in every patient. Only 16.6% perform open lung biopsy or thoracoscopic biopsy in all or most of their patients. Sixty eight percent of physicians who always have availability of DLCO perform it in every patient but only 7.1% of those who seldom have access to DLCO do so (p = 0.0003). Availability of bronchoscopy does not have any influence on the decision of performing BAL or transbronchial biopsy. Frequency of use of surgical biopsy or treatment with immunosuppressive drugs was not influenced by any variable. We conclude that there is a current trend to underuse diagnostic resources for ILD in Argentina. Limitations in availability are relevant regarding DLCO. An effort from the health authorities to centralize the management of patients with ILD would allow to study and treat them according to international recommendations.

  5. DNA Barcoding Identifies Argentine Fishes from Marine and Brackish Waters

    PubMed Central

    Mabragaña, Ezequiel; Díaz de Astarloa, Juan Martín; Hanner, Robert; Zhang, Junbin; González Castro, Mariano

    2011-01-01

    Background DNA barcoding has been advanced as a promising tool to aid species identification and discovery through the use of short, standardized gene targets. Despite extensive taxonomic studies, for a variety of reasons the identification of fishes can be problematic, even for experts. DNA barcoding is proving to be a useful tool in this context. However, its broad application is impeded by the need to construct a comprehensive reference sequence library for all fish species. Here, we make a regional contribution to this grand challenge by calibrating the species discrimination efficiency of barcoding among 125 Argentine fish species, representing nearly one third of the known fauna, and examine the utility of these data to address several key taxonomic uncertainties pertaining to species in this region. Methodology/Principal Findings Specimens were collected and morphologically identified during crusies conducted between 2005 and 2008. The standard BARCODE fragment of COI was amplified and bi-directionally sequenced from 577 specimens (mean of 5 specimens/species), and all specimens and sequence data were archived and interrogated using analytical tools available on the Barcode of Life Data System (BOLD; www.barcodinglife.org). Nearly all species exhibited discrete clusters of closely related haplogroups which permitted the discrimination of 95% of the species (i.e. 119/125) examined while cases of shared haplotypes were detected among just three species-pairs. Notably, barcoding aided the identification of a new species of skate, Dipturus argentinensis, permitted the recognition of Genypterus brasiliensis as a valid species and questions the generic assignment of Paralichthys isosceles. Conclusions/Significance This study constitutes a significant contribution to the global barcode reference sequence library for fishes and demonstrates the utility of barcoding for regional species identification. As an independent assessment of alpha taxonomy, barcodes provide

  6. Seasonal food habits of swift fox (Vulpes velox) in cropland and rangeland landscapes in western Kansas

    USGS Publications Warehouse

    Sovada, M.A.; Roy, C.C.; Telesco, D.J.

    2001-01-01

    Food habits of swift foxes (Vulpes velox) occupying two distinct landscapes (dominated by cropland versus rangeland) in western Kansas were determined by analysis of scats collected in 1993 and 1996. Frequencies of occurrence of prey items in scats were compared between cropland and rangeland areas by season. Overall, the most frequently occurring foods of swift foxes were mammals (92% of all scats) and arthropods (87%), followed by birds (24%), carrion (23%), plants (15%) and reptiles (4%). No differences were detected between landscapes for occurrence of mammals, arthropods or carrion in any season (P ??? 0.100). Plants, specifically commercial sunflower seeds, were consumed more frequently in cropland than in rangeland in spring (P = 0.004) and fall (P = 0.001). Birds were more common in the swift fox diet in cropland than in rangeland during the fall (P = 0.008), whereas reptiles occurred more frequently in the diet in rangeland than in cropland during spring (P = 0.042). Variation in the diet of the swift fox between areas was most likely due to its opportunistic foraging behavior, resulting in a diet that closely links prey use with availability.

  7. Reorienting land degradation towards sustainable land management: linking sustainable livelihoods with ecosystem services in rangeland systems.

    PubMed

    Reed, M S; Stringer, L C; Dougill, A J; Perkins, J S; Atlhopheng, J R; Mulale, K; Favretto, N

    2015-03-15

    This paper identifies new ways of moving from land degradation towards sustainable land management through the development of economic mechanisms. It identifies new mechanisms to tackle land degradation based on retaining critical levels of natural capital whilst basing livelihoods on a wider range of ecosystem services. This is achieved through a case study analysis of the Kalahari rangelands in southwest Botswana. The paper first describes the socio-economic and ecological characteristics of the Kalahari rangelands and the types of land degradation taking place. It then focuses on bush encroachment as a way of exploring new economic instruments (e.g. Payments for Ecosystem Services) designed to enhance the flow of ecosystem services that support livelihoods in rangeland systems. It does this by evaluating the likely impacts of bush encroachment, one of the key forms of rangeland degradation, on a range of ecosystem services in three land tenure types (private fenced ranches, communal grazing areas and Wildlife Management Areas), before considering options for more sustainable land management in these systems. We argue that with adequate policy support, economic mechanisms could help reorient degraded rangelands towards more sustainable land management.

  8. Integrating dynamic soil and vegetation properties into ecosystem service-based state and transition models to guide rangeland management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    California’s annual rangelands cover approximately 6.4 million hectares, and produce 70% of the state’s forage base. This ecosystem supports more than 300 vertebrate, 5000 invertebrate, and 2000 plant species. Annual rangeland soils have the capacity to support high primary productivity, accumulate ...

  9. Grazing impacts on the susceptibility of rangelands to wind erosion: the effects of stocking rate, stocking strategy and land condition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An estimated 110 Mt of dust is eroded by wind from the Australian land surface each year, most of which originates from the arid and semi-arid rangelands. Livestock production is thought to increase the susceptibility of the rangelands to wind erosion by reducing vegetation cover and modifying surfa...

  10. Precipitation regulates the response of net ecosystem CO2 exchange to environmental variation on U.S. rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangelands occupy about 50% of the Earth’s land surface and thus play an important role in the terrestrial carbon (C) cycle. For rangelands and other terrestrial ecosystems, the balance between photosynthetic uptake of carbon dioxide (CO2) and CO2 loss to respiration varies among years in response ...

  11. State and transition models: Theory, applications, and challenges. In: Briske, D.D. Rangeland Systems: Processes, Management and Challenges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    State and transition models (STMs) are used for communicating about ecosystem change in rangelands and other ecosystems, especially the implications for management. The fundamental premise that rangelands can exhibit multiple states is now widely accepted. The current application of STMs for managem...

  12. Using common gardens and AFLP analyses to identify metapopulations of indigenous plant materials for rangeland revegetation in western USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Semiarid rangelands in the western USA are facing unprecedented challenges related to past mismanagement, invasive weedy species, wildfires, and climatic change. A diversity of plant species are needed to effectively revegetate these rangelands. Legumes indigenous to western North America are of p...

  13. Hierarchical object-based classification of ultra-high-resolution digital mapping camera (DMC) imagery for rangeland mapping and assessment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ultra high resolution digital aerial photography has great potential to complement or replace ground measurements of vegetation cover for rangeland monitoring and assessment. We investigated object-based image analysis (OBIA) techniques for classifying vegetation in southwestern U.S. arid rangelands...

  14. Modeling vegetation heights from high resolution stereo aerial photography: an application for broad-scale rangeland monitoring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vertical vegetation structure in rangeland ecosystems can be a valuable indicator for monitoring rangeland health or progress toward management objectives because of its importance for assessing riparian areas, post-fire recovery, wind erosion, and wildlife habitat. Federal land management agencies ...

  15. Risk assessment of erosion from concentrated flow on rangelands using overland flow distribution and shear stress partitioning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Erosion rates of overland flow on rangelands tend to be relatively low, but under certain conditions where flow is concentrated, soil loss can be significant. Therefore, a rangeland site can be highly vulnerable to soil erosion where overland flow is likely to concentrate and exert high shear stress...

  16. Deriving shrub heights from high resolution stereo-pair aerial imagery: An application for broad-scale rangeland monitoring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vertical vegetation structure in rangeland ecosystems can be a valuable indicator for monitoring rangeland health or progress toward management objectives because of its importance for assessing riparian areas, post-fire recovery, wind erosion, and wildlife habitat. Federal land management agencies ...

  17. A suite of tools for monitoring and assessing impacts of road networks and off-road vehicle activity on rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite increasing amounts of transportation related activities on rangelands globally, few tools exist for assessing and monitoring impacts of roads, road networks and off-road vehicle traffic. This is in part due to an historical emphasis on grazing issues in rangelands and the complexity of monit...

  18. Identifying geographically based metapopulations for development of plant materials indigenous to rangeland ecosystems of the western USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland ecosystems account for about half of the earth's land surface. They play an important role in providing forage for livestock and wildlife, and they serve as critical watershed areas. Many of the world's rangelands have been degraded by overgrazing, marginal crop production, mineral and e...

  19. Ecological site-based assessments of wind and water erosion: Informing accelerated soil erosion management in rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper explores how soil erosion assessments structured across ecological sites can inform systems for managing accelerated soil erosion in rangelands. We evaluated wind and water erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wi...

  20. Effects of grazing exclusion on soil properties and on ecosystem carbon and nitrogen storage in a sandy rangeland of Inner Mongolia, northern China.

    PubMed

    Chen, Yinping; Li, Yuqiang; Zhao, Xueyong; Awada, Tala; Shang, Wen; Han, Juanjuan

    2012-10-01

    The Horqin sandy rangeland of northern China is a seriously desertified region with a fragile ecology. The sandy alluvial and aeolian sediments have a coarse texture and loose structure and are therefore vulnerable to damage caused by grazing animals and wind erosion. We investigated whether grazing exclusion could enhance ecosystem carbon (C) and nitrogen (N) storage and thereby improve overall soil quality. We compared soil properties, C and N storage in biomass (aboveground and below-ground), and the total and light fraction soil organic matter between adjacent areas with continuous grazing and a 12-year grazing exclosure. The soil silt + clay content, organic C, total Kjeldahl N, available N and K, and cation-exchange capacity were significantly (P < 0.05) greater in the exclosure. We found that to a depth of 100 cm, the exclosure plots had greater light fraction C storage (by 267.2 g m(-2) = 73.3 %), light fraction N storage (by 16.6 g m(-2) = 105.7 %), total soil C storage (by 1174.4 g m(-2) = 43.9 %), and total N storage (by 91.1 g m(-2) = 31.3 %). Biomass C and N storage were also 205.0 and 8.0 g m(-2) greater (154.8 and 181.8 %, respectively). The increase was greatest in the light fraction organic matter and biomass and decreased with increasing depth in the soil. The results suggest that light fraction C and N respond more rapidly than total soil C and N to grazing exclusion and that vegetation recovers faster than soil. Our results confirmed that the degraded sandy rangeland is recovering and sequestering C after the removal of grazing pressure.

  1. The 2014 National Emission Inventory for Rangeland Fires ...

    EPA Pesticide Factsheets

    Biomass burning has been identified as an important contributor to the degradation of air quality because of its impact on ozone and particulate matter. One component of the biomass burning inventory, crop residue burning, has been poorly characterized in the National Emissions Inventory. In the 2011 NEI, Wildland fires, prescribed fires, and crop residue burning collectively were the largest source of PM2.5 This paper summarizes our 2014 NEI method to estimate crop residue burning emissions and grass/pasture burning emissions using remote sensing data and field information and literature-based, crop-specific emission factors. We will focus on both the post-harvest and pre-harvest burning that takes place with bluegrass, corn, cotton, rice, soybeans, sugarcane and wheat. Estimates for 2014 indicate that over the continental United States (CONUS), crop residue burning including all areas identified as Pasture/Grass, Grassland Herbaceous, and Pasture/Hay produced 64,994 short tons of PM2.5. This estimate compares with the 2011 NEI and 2008 NEI as follows: 2008: 49,653 short tons and 2011: 141,184 short tons. Note that in the previous two NEI’s rangeland burning was not well-defined and so the comparison is not exact. In addition, the entire database used to estimate this sector of emissions is available on EPA’s Clearinghouse for Inventories and Emission Factors (CHIEF http://www3.epa.gov/ttn/chief/index.html The National Emissions Inventory is developed on

  2. Prediction methodology for contaminant transport from rangeland watersheds

    SciTech Connect

    Devaurs, M.A.; Springer, E.P.; Lane, L.J.; Langhorst, G.J.

    1988-01-01

    Weather on arid and semiarid lands can be extremely variable. Runoff is generally emphermeral, and high intensity, short-duration rainfall events are the major stimulus for runoff events. Transport of sediment and associated contaminants occurs with these infrequent events. Incorporation of variability in weather into any prediction technology is essential to provide accurate representations of climate-induced uncertainty in predictions of hydrologic response. The objective of this study is to investigate a method for including short-term climatic variations in analyses for contaminant transport from rangeland watersheds in arid/semiarid regions. Short term is defined here as a twenty to fifty time frame and it is assumed that lone term climatic fluctuations are not observed during this time. Also, most weather records are available for this time period; predictions of greater length are extrapolations of existing records unless corroborative data for longer term trends are collected. Predictions are being made with condensable uncertainty in the weather inputs even if the models for water, sediment, and contaminant transport are perfectly unknown. This study will incorporate uncertainty in weather inputs into the prediction process and address the ramifications of this uncertainty. Uncertainty introduced by improper model or parameter specification is only briefly addressed.

  3. Using 70-mm aerial photography to identify rangeland sites

    NASA Technical Reports Server (NTRS)

    Everitt, J. H.; Gerbermann, A. H.; Alaniz, M. A.; Bowen, R. L.

    1980-01-01

    A south Texas rangeland area was used as a study site to test the use of microdensitometry on 70-mm color-infrared and black-and-white photographs (scale 1:19,000) for distinguishing among 11 range sites (two brushland, seven grassland, two barren land) during the winter (February), spring (May), and summer (August) of 1976. Color-infrared photographs were also taken at a scale of 1:42,000 for the summer date. Film optical density readings were made on one color-infrared film with white light only. The best separations among density readings for all range sites were obtained using white light exposed on color-infrared film in the summer when vegetation was at peak foliage development. Results from this study indicate that 70-mm aerial color-infrared photography at a scale of 1:19,000 or 1:42,000 has good potential for identifying range sites in large and inaccessible areas, and could be a useful tool for range management.

  4. Assessing the Success of Postfire Reseeding in Semiarid Rangelands Using Terra MODIS

    NASA Technical Reports Server (NTRS)

    Chen, Fang; Weber, Keith T.; Scbnase, John L.

    2012-01-01

    Successful postfire reseeding efforts can aid rangeland ecosystem recovery by rapidly establishing a desired plant community and thereby reducing the likelihood of infestation by invasive plants. Although the success of postfire remediation is critical, few efforts have been made to leverage existing geospatial technologies to develop methodologies to assess reseeding success following a fire. In this study, Terra Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data were used to improve the capacity to assess postfire reseeding rehabilitation efforts, with particular emphasis on the semiarid rangelands of Idaho. Analysis of MODIS data demonstrated a positive effect of reseeding on rangeland ecosystem recovery, as well as differences in vegetation between reseeded areas and burned areas where no reseeding had occurred (P,0.05). We conclude that MODIS provides useful data to assess the success of postfire reseeding.

  5. Carrying capacity in arid rangelands during droughts: the role of temporal and spatial thresholds.

    PubMed

    Accatino, F; Ward, D; Wiegand, K; De Michele, C

    2017-02-01

    Assessing the carrying capacity is of primary importance in arid rangelands. This becomes even more important during droughts, when rangelands exhibit non-equilibrium dynamics, and the dynamics of livestock conditions and forage resource are decoupled. Carrying capacity is usually conceived as an equilibrium concept, that is, the consumer density that can co-exist in long-term equilibrium with the resource. As one of the first, here we address the concept of carrying capacity in systems, where there is no feedback between consumer and resource in a limited period of time. To this end, we developed an individual-based model describing the basic characteristics of a rangeland during a drought. The model represents a rangeland composed by a single water point and forage distributed all around, with livestock units moving from water to forage and vice versa, for eating and drinking. For each livestock unit we implemented an energy balance and we accounted for the gut-filling effect (i.e. only a limited amount of forage can be ingested per unit time). Our results showed that there is a temporal threshold above which livestock begin to experience energy deficit and burn fat reserves. We demonstrated that such a temporal threshold increases with the number of animals and decreases with the rangeland conditions (amount of forage). The temporal threshold corresponded to the time livestock take to consume all the forage within a certain distance from water, so that the livestock can return to water for drinking without spending more energy than they gain within a day. In this study, we highlight the importance of a time threshold in the assessment of carrying capacity in non-equilibrium conditions. Considering this time threshold could explain contrasting observations about the influence of livestock number on livestock conditions. In case of private rangelands, the herd size should be chosen so that the spatial threshold equals (or exceeds) the length of the drought.

  6. Rangeland dynamics: investigating vegetation composition and structure of urban and exurban prairie dog habitat

    PubMed Central

    Hopson, Rebecca; Meiman, Paul

    2015-01-01

    Rapid human population growth and habitat modification in the western United States has led to the formation of urban and exurban rangelands. Many of these rangelands are also home to populations of black-tailed prairie dogs (Cynomys ludovicianus). Our study aimed to compare the vegetation composition of an urban and exurban rangeland, and explore the role that prairie dogs play in these systems. The percent absolute canopy cover of graminoids (grasses and grass-likes), forbs, shrubs, litter, and bare ground were estimated at sampling areas located on and off prairie dog colonies at an urban and an exurban site. Herbaceous forage quality and quantity were determined on plant material collected from exclosure cages located on the colony during the entire growing season, while a relative estimate of prairie dog density was calculated using maximum counts. The exurban site had more litter and plant cover and less bare ground than the urban site. Graminoids were the dominant vegetation at the exurban plots. In contrast, mostly introduced forbs were found on the urban prairie dog colony. However, the forage quality and quantity tests demonstrated no difference between the two colonies. The relative prairie dog density was greater at the urban colony, which has the potential to drive greater vegetation utilization and reduced cover. Exurban rangeland showed lower levels of impact and retained all of the plant functional groups both on- and off-colony. These results suggest that activities of prairie dogs might further exacerbate the impacts of humans in fragmented urban rangeland habitats. Greater understanding of the drivers of these impacts and the spatial scales at which they occur are likely to prove valuable in the management and conservation of rangelands in and around urban areas. PMID:25650011

  7. Biomass Increases Go under Cover: Woody Vegetation Dynamics in South African Rangelands

    PubMed Central

    Mograbi, Penelope J.; Knapp, David E.; Martin, Roberta E.; Main, Russell

    2015-01-01

    Woody biomass dynamics are an expression of ecosystem function, yet biomass estimates do not provide information on the spatial distribution of woody vegetation within the vertical vegetation subcanopy. We demonstrate the ability of airborne light detection and ranging (LiDAR) to measure aboveground biomass and subcanopy structure, as an explanatory tool to unravel vegetation dynamics in structurally heterogeneous landscapes. We sampled three communal rangelands in Bushbuckridge, South Africa, utilised by rural communities for fuelwood harvesting. Woody biomass estimates ranged between 9 Mg ha-1 on gabbro geology sites to 27 Mg ha-1 on granitic geology sites. Despite predictions of woodland depletion due to unsustainable fuelwood extraction in previous studies, biomass in all the communal rangelands increased between 2008 and 2012. Annual biomass productivity estimates (10–14% p.a.) were higher than previous estimates of 4% and likely a significant contributor to the previous underestimations of modelled biomass supply. We show that biomass increases are attributable to growth of vegetation <5 m in height, and that, in the high wood extraction rangeland, 79% of the changes in the vertical vegetation subcanopy are gains in the 1-3m height class. The higher the wood extraction pressure on the rangelands, the greater the biomass increases in the low height classes within the subcanopy, likely a strong resprouting response to intensive harvesting. Yet, fuelwood shortages are still occurring, as evidenced by the losses in the tall tree height class in the high extraction rangeland. Loss of large trees and gain in subcanopy shrubs could result in a structurally simple landscape with reduced functional capacity. This research demonstrates that intensive harvesting can, paradoxically, increase biomass and this has implications for the sustainability of ecosystem service provision. The structural implications of biomass increases in communal rangelands could be

  8. Biomass Increases Go under Cover: Woody Vegetation Dynamics in South African Rangelands.

    PubMed

    Mograbi, Penelope J; Erasmus, Barend F N; Witkowski, E T F; Asner, Gregory P; Wessels, Konrad J; Mathieu, Renaud; Knapp, David E; Martin, Roberta E; Main, Russell

    2015-01-01

    Woody biomass dynamics are an expression of ecosystem function, yet biomass estimates do not provide information on the spatial distribution of woody vegetation within the vertical vegetation subcanopy. We demonstrate the ability of airborne light detection and ranging (LiDAR) to measure aboveground biomass and subcanopy structure, as an explanatory tool to unravel vegetation dynamics in structurally heterogeneous landscapes. We sampled three communal rangelands in Bushbuckridge, South Africa, utilised by rural communities for fuelwood harvesting. Woody biomass estimates ranged between 9 Mg ha(-1) on gabbro geology sites to 27 Mg ha(-1) on granitic geology sites. Despite predictions of woodland depletion due to unsustainable fuelwood extraction in previous studies, biomass in all the communal rangelands increased between 2008 and 2012. Annual biomass productivity estimates (10-14% p.a.) were higher than previous estimates of 4% and likely a significant contributor to the previous underestimations of modelled biomass supply. We show that biomass increases are attributable to growth of vegetation <5 m in height, and that, in the high wood extraction rangeland, 79% of the changes in the vertical vegetation subcanopy are gains in the 1-3 m height class. The higher the wood extraction pressure on the rangelands, the greater the biomass increases in the low height classes within the subcanopy, likely a strong resprouting response to intensive harvesting. Yet, fuelwood shortages are still occurring, as evidenced by the losses in the tall tree height class in the high extraction rangeland. Loss of large trees and gain in subcanopy shrubs could result in a structurally simple landscape with reduced functional capacity. This research demonstrates that intensive harvesting can, paradoxically, increase biomass and this has implications for the sustainability of ecosystem service provision. The structural implications of biomass increases in communal rangelands could be

  9. A Rangeland Hydrology and Erosion Model for Developing Ecological Site Descriptions

    NASA Astrophysics Data System (ADS)

    Nearing, M. A.; Hernandez, M.; Armendariz, G.; Barker, S.; Williams, C. J.

    2014-12-01

    Predicting soil erosion is common practice in natural resource management for assessing the effects of management practices and control techniques of soil productivity, sediment delivery and off site water quality. The Rangeland Hydrology and Erosion Model (RHEM) was designed for this purpose. RHEM is an event-based model that estimates runoff, erosion, and sediment delivery rates and volumes at the spatial scale of the hillslope and the temporal scale of as single rainfall event. It represents erosion processes under normal and fire-impacted rangeland conditions. Moreover, it adopts a new splash erosion and thin sheet -flow transport equation developed from rangeland data, and it links the model hydrologic and erosion parameters with rangeland plant community by providing a new system of parameter estimation equations based on 204 plots at 49 rangeland sites distributed across 15 western U.S. states. Testing was done using long-term runoff and erosion data from small semi-aridland catchments. One of our goals with this project is to develop a framework for incorporating key ecohydrologic information/relationships in Ecological Site Descriptions and thereby enhanced utility of Ecological Site Descriptions s for guiding management. These key ecohydrologic relationships govern the ecologic resilience of the various states and community phases on many rangeland ecological sites and are strongly affected by management practices, land use, and disturbances. However, ecohydrologic data and relationships are often missing in Ecological Site Descriptions and resilience-based state-and-transition models. In this study we applied the RHEM model to data from multiple points in several ecological sites in Arizona, New Mexico, and Utah to assess the utility of the model for informing these Ecological Site Descriptions.

  10. Schooling and Governance: Pedagogical Knowledge and Bureaucratic Expertise in the Genesis of the Argentine Educational System

    ERIC Educational Resources Information Center

    Southwell, Myriam

    2013-01-01

    The consolidation of the Argentine Federal Government by the 1870s aimed to modernise local society, establish state institutions and reach political stabilisation. Building a modern schooling system articulated both utopia and bureaucracy by establishing the use of knowledge as an instrument of social intervention, vindicating and legitimising…

  11. Draft genome of the globally widespread and invasive Argentine ant (Linepithema humile)

    PubMed Central

    Smith, Christopher D.; Zimin, Aleksey; Holt, Carson; Abouheif, Ehab; Benton, Richard; Cash, Elizabeth; Croset, Vincent; Currie, Cameron R.; Elhaik, Eran; Elsik, Christine G.; Fave, Marie-Julie; Fernandes, Vilaiwan; Gadau, Jürgen; Gibson, Joshua D.; Graur, Dan; Grubbs, Kirk J.; Hagen, Darren E.; Helmkampf, Martin; Holley, Jo-Anne; Hu, Hao; Viniegra, Ana Sofia Ibarraran; Johnson, Brian R.; Johnson, Reed M.; Khila, Abderrahman; Kim, Jay W.; Laird, Joseph; Mathis, Kaitlyn A.; Moeller, Joseph A.; Muñoz-Torres, Monica C.; Murphy, Marguerite C.; Nakamura, Rin; Nigam, Surabhi; Overson, Rick P.; Placek, Jennifer E.; Rajakumar, Rajendhran; Reese, Justin T.; Robertson, Hugh M.; Suarez, Andrew V.; Suen, Garret; Suhr, Elissa L.; Tao, Shu; Torres, Candice W.; van Wilgenburg, Ellen; Viljakainen, Lumi; Walden, Kimberly K. O.; Wild, Alexander L.; Yandell, Mark; Yorke, James A.; Tsutsui, Neil D.

    2011-01-01

    Ants are some of the most abundant and familiar animals on Earth, and they play vital roles in most terrestrial ecosystems. Although all ants are eusocial, and display a variety of complex and fascinating behaviors, few genomic resources exist for them. Here, we report the draft genome sequence of a particularly widespread and well-studied species, the invasive Argentine ant (Linepithema humile), which was accomplished using a combination of 454 (Roche) and Illumina sequencing and community-based funding rather than federal grant support. Manual annotation of >1,000 genes from a variety of different gene families and functional classes reveals unique features of the Argentine ant's biology, as well as similarities to Apis mellifera and Nasonia vitripennis. Distinctive features of the Argentine ant genome include remarkable expansions of gustatory (116 genes) and odorant receptors (367 genes), an abundance of cytochrome P450 genes (>110), lineage-specific expansions of yellow/major royal jelly proteins and desaturases, and complete CpG DNA methylation and RNAi toolkits. The Argentine ant genome contains fewer immune genes than Drosophila and Tribolium, which may reflect the prominent role played by behavioral and chemical suppression of pathogens. Analysis of the ratio of observed to expected CpG nucleotides for genes in the reproductive development and apoptosis pathways suggests higher levels of methylation than in the genome overall. The resources provided by this genome sequence will offer an abundance of tools for researchers seeking to illuminate the fascinating biology of this emerging model organism. PMID:21282631

  12. Draft genome of the globally widespread and invasive Argentine ant (Linepithema humile).

    PubMed

    Smith, Christopher D; Zimin, Aleksey; Holt, Carson; Abouheif, Ehab; Benton, Richard; Cash, Elizabeth; Croset, Vincent; Currie, Cameron R; Elhaik, Eran; Elsik, Christine G; Fave, Marie-Julie; Fernandes, Vilaiwan; Gadau, Jürgen; Gibson, Joshua D; Graur, Dan; Grubbs, Kirk J; Hagen, Darren E; Helmkampf, Martin; Holley, Jo-Anne; Hu, Hao; Viniegra, Ana Sofia Ibarraran; Johnson, Brian R; Johnson, Reed M; Khila, Abderrahman; Kim, Jay W; Laird, Joseph; Mathis, Kaitlyn A; Moeller, Joseph A; Muñoz-Torres, Monica C; Murphy, Marguerite C; Nakamura, Rin; Nigam, Surabhi; Overson, Rick P; Placek, Jennifer E; Rajakumar, Rajendhran; Reese, Justin T; Robertson, Hugh M; Smith, Chris R; Suarez, Andrew V; Suen, Garret; Suhr, Elissa L; Tao, Shu; Torres, Candice W; van Wilgenburg, Ellen; Viljakainen, Lumi; Walden, Kimberly K O; Wild, Alexander L; Yandell, Mark; Yorke, James A; Tsutsui, Neil D

    2011-04-05

    Ants are some of the most abundant and familiar animals on Earth, and they play vital roles in most terrestrial ecosystems. Although all ants are eusocial, and display a variety of complex and fascinating behaviors, few genomic resources exist for them. Here, we report the draft genome sequence of a particularly widespread and well-studied species, the invasive Argentine ant (Linepithema humile), which was accomplished using a combination of 454 (Roche) and Illumina sequencing and community-based funding rather than federal grant support. Manual annotation of >1,000 genes from a variety of different gene families and functional classes reveals unique features of the Argentine ant's biology, as well as similarities to Apis mellifera and Nasonia vitripennis. Distinctive features of the Argentine ant genome include remarkable expansions of gustatory (116 genes) and odorant receptors (367 genes), an abundance of cytochrome P450 genes (>110), lineage-specific expansions of yellow/major royal jelly proteins and desaturases, and complete CpG DNA methylation and RNAi toolkits. The Argentine ant genome contains fewer immune genes than Drosophila and Tribolium, which may reflect the prominent role played by behavioral and chemical suppression of pathogens. Analysis of the ratio of observed to expected CpG nucleotides for genes in the reproductive development and apoptosis pathways suggests higher levels of methylation than in the genome overall. The resources provided by this genome sequence will offer an abundance of tools for researchers seeking to illuminate the fascinating biology of this emerging model organism.

  13. Argentine Hydrellia Robineau-Desvoidy (Diptera, Ephydridae): new species and key to identification.

    PubMed

    Rodrigues Júnior, Francisco De Assis; Mathis, Wayne Nielsen; Hauser, Martin

    2015-05-13

    Hydrellia egeriae sp. nov., a new species of Hydrellia from Campana (34 14' 04 S, 58 52' 32 W) and Hurlingham (3435'14 S, 5838'27 W), Buenos Aires province, Argentina is described. A key to the Argentine Hydrellia species is presented.

  14. Experimental warming, not grazing, decreases rangeland quality on the Tibetan Plateau.

    PubMed

    Klein, Julia A; Harte, John; Zhao, Xin-Quan

    2007-03-01

    We investigated experimental warming and simulated grazing (clipping) effects on rangeland quality, as indicated by vegetation production and nutritive quality, in winter-grazed meadows and summer-grazed shrublands on the Tibetan Plateau, a rangeland system experiencing climatic and pastoral land use changes. Warming decreased total aboveground net primary productivity (ANPP) by 40 g x m(-2) x yr(-1) at the meadow habitats and decreased palatable ANPP (total ANPP minus non-palatable forb ANPP) by 10 g x m(-2) x yr(-1) at both habitats. The decreased production of the medicinal forb Gentiana straminea and the increased production of the non-palatable forb Stellera chamaejasme with warming also reduced rangeland quality. At the shrubland habitats, warming resulted in less digestible shrubs, whose foliage contains 25% digestible dry matter (DDM), replacing more digestible graminoids, whose foliage contains 60% DDM. This shift from graminoids to shrubs not only results in lower-quality forage, but could also have important consequences for future domestic herd composition. Although warming extended the growing season in non-clipped plots, the reduced rangeland quality due to decreased vegetative production and nutritive quality will likely overwhelm the improved rangeland quality associated with an extended growing season. Grazing maintained or improved rangeland quality by increasing total ANPP by 20-40 g x m(-2) x yr(-1) with no effect on palatable ANPP. Grazing effects on forage nutritive quality, as measured by foliar nitrogen and carbon content and by shifts in plant group ANPP, resulted in improved forage quality. Grazing extended the growing season at both habitats, and it advanced the growing season at the meadows. Synergistic interactions between warming and grazing were present, such that grazing mediated the warming-induced declines in vegetation production and nutritive quality. Moreover, combined treatment effects were nonadditive, suggesting that we

  15. Evaluating new SMAP soil moisture for drought monitoring in the rangelands of the US High Plains

    USGS Publications Warehouse

    Velpuri, Naga Manohar; Senay, Gabriel B.; Morisette, Jeffrey T.

    2016-01-01

    Level 3 soil moisture datasets from the recently launched Soil Moisture Active Passive (SMAP) satellite are evaluated for drought monitoring in rangelands.Validation of SMAP soil moisture (SSM) with in situ and modeled estimates showed high level of agreement.SSM showed the highest correlation with surface soil moisture (0-5 cm) and a strong correlation to depths up to 20 cm.SSM showed a reliable and expected response of capturing seasonal dynamics in relation to precipitation, land surface temperature, and evapotranspiration.Further evaluation using multi-year SMAP datasets is necessary to quantify the full benefits and limitations for drought monitoring in rangelands.

  16. Process for recovering actinide values

    DOEpatents

    Horwitz, E. Philip; Mason, George W.

    1980-01-01

    A process for rendering actinide values recoverable from sodium carbonate scrub waste solutions containing these and other values along with organic compounds resulting from the radiolytic and hydrolytic degradation of neutral organophosphorous extractants such as tri-n butyl phosphate (TBP) and dihexyl-N,N-diethyl carbamylmethylene phosphonate (DHDECAMP) which have been used in the reprocessing of irradiated nuclear reactor fuels. The scrub waste solution is preferably made acidic with mineral acid, to form a feed solution which is then contacted with a water-immiscible, highly polar organic extractant which selectively extracts the degradation products from the feed solution. The feed solution can then be processed to recover the actinides for storage or recycled back into the high-level waste process stream. The extractant is recycled after stripping the degradation products with a neutral sodium carbonate solution.

  17. Process for recovering acidic gases

    SciTech Connect

    Riggs, O.L. Jr.

    1989-09-26

    This patent describes an improvement in a continuous process for recovering carbon dioxide from a carbon dioxide-rich gas stream. The gas stream is contacted with an aqueous alknolamine solution in an absorption section contained in an absorption zone to produce a carbon dioxide-lean gaseous overhead stream and a carbon dioxide-rich liquid effluent stream. The carbon dioxide-rich effluent stream is heated in a regeneration zone to produce a carbon dioxide-rich gaseous overhead stream and a carbon dioxide-lean liquid effluent stream. The carbon dioxide-lean liquid effluent stream comprising a regenerated aqueous alkanolamine solution. The regenerated aqueous alkanolamine solution is returned to and introduced into the absorption zone.

  18. METHOD OF RECOVERING URANIUM COMPOUNDS

    DOEpatents

    Poirier, R.H.

    1957-10-29

    S>The recovery of uranium compounds which have been adsorbed on anion exchange resins is discussed. The uranium and thorium-containing residues from monazite processed by alkali hydroxide are separated from solution, and leached with an alkali metal carbonate solution, whereby the uranium and thorium hydrorides are dissolved. The carbonate solution is then passed over an anion exchange resin causing the uranium to be adsorbed while the thorium remains in solution. The uranium may be recovered by contacting the uranium-holding resin with an aqueous ammonium carbonate solution whereby the uranium values are eluted from the resin and then heating the eluate whereby carbon dioxide and ammonia are given off, the pH value of the solution is lowered, and the uranium is precipitated.

  19. Powerful motors: Kinship, citizenship and the transformation of the Argentine oil industry

    NASA Astrophysics Data System (ADS)

    Shever, Elana

    The privatization of the Argentine oil industry has been described as an unprecedented transfer of property, capital and control from the state to the corporate sphere, but this study demonstrates that the privatization process is better understood as a transformation of the historical configurations of oil-fueled development, political communities and human subjectivities. This dissertation probes the development of the state-led oil industry, and the shift to a corporate-led one, through an ethnography of Argentines differently positioned in relation to the global oil industry. The ethnography explores the lives of middle class oil workers and their families in Northwest Patagonia, impoverished residents of the shanty neighborhoods near the refineries in metropolitan Buenos Aires, and affluent employees of the translocal corporations operating in the Argentine oil fields. After the Introduction delineates this study's four principal interventions into anthropological scholarship, each subsequent chapter engages a particular problem that cuts across the Argentine oil fields and the anthropological theoretical fields. Chapter Two scrutinizes the historical construction of the Argentine subterritory as a "natural" space of value. Chapters Three and Four investigate the articulation of capitalist production and filial reproduction. These chapters argue that sentiment is a crucial generative force that has shaped the oil industry, company towns and worker families from the founding of the state-owned oil company in beginning of the twentieth century to its conversion into a corporate-owned one at the century's close. Chapters Five and Six examine the emergence of consumer citizenship and corporate citizenship out of Argentine neoliberalismo and its transformation of the oil industry. They argue that consumer and corporate citizenship are both reformulations of the older traditions of liberalism and Peronism. All the chapters of this dissertation illustrate that the

  20. Trophic ecology of invasive Argentine ants in their native and introduced ranges.

    PubMed

    Tillberg, Chadwick V; Holway, David A; Lebrun, Edward G; Suarez, Andrew V

    2007-12-26

    Although the ecological effects of invasions often become obvious soon after introduced species become established, more gradual effects may take years to manifest and can thus require long-term data for quantification. We analyzed an 8-year record of stable isotope data on Argentine ants (Linepithema humile) from southern California to infer how the trophic position of this widespread invasive species changes over time as native ant species are displaced. We couple this longitudinal analysis with a biregional comparison of stable isotope data (delta(15)N) on ants from Argentina (native range) and California (introduced range) to quantify (i) how the trophic position of L. humile differs between native and introduced populations, and (ii) how relative trophic position as estimated by delta(15)N values of Argentine ants compare with those of other ants at the same site. Both long-term and biregional comparisons indicate that the Argentine ant's relative trophic position is reduced at sites with a longer history of occupation. Over the course of 8 years, the relative trophic position of L. humile remained high at the leading edge of an invasion front but declined, on average, behind the front as native ants disappeared. Relative to native populations, where L. humile is among the most carnivorous of ants, Argentine ants from California occupied lower trophic positions. These results support the hypothesis that Argentine ants shift their diet after establishment as a result of resource depletion and increasing reliance on plant-based resources, especially honeydew-producing Hemiptera. Our results demonstrate the value of long-term and biregional data in uncovering ecological effects of invasions.

  1. Trophic ecology of invasive Argentine ants in their native and introduced ranges

    PubMed Central

    Tillberg, Chadwick V.; Holway, David A.; LeBrun, Edward G.; Suarez, Andrew V.

    2007-01-01

    Although the ecological effects of invasions often become obvious soon after introduced species become established, more gradual effects may take years to manifest and can thus require long-term data for quantification. We analyzed an 8-year record of stable isotope data on Argentine ants (Linepithema humile) from southern California to infer how the trophic position of this widespread invasive species changes over time as native ant species are displaced. We couple this longitudinal analysis with a biregional comparison of stable isotope data (δ15N) on ants from Argentina (native range) and California (introduced range) to quantify (i) how the trophic position of L. humile differs between native and introduced populations, and (ii) how relative trophic position as estimated by δ15N values of Argentine ants compare with those of other ants at the same site. Both long-term and biregional comparisons indicate that the Argentine ant's relative trophic position is reduced at sites with a longer history of occupation. Over the course of 8 years, the relative trophic position of L. humile remained high at the leading edge of an invasion front but declined, on average, behind the front as native ants disappeared. Relative to native populations, where L. humile is among the most carnivorous of ants, Argentine ants from California occupied lower trophic positions. These results support the hypothesis that Argentine ants shift their diet after establishment as a result of resource depletion and increasing reliance on plant-based resources, especially honeydew-producing Hemiptera. Our results demonstrate the value of long-term and biregional data in uncovering ecological effects of invasions. PMID:18093925

  2. Recovering Radioactive Materials with OSRP team

    SciTech Connect

    2008-04-30

    The National Nuclear Security Administration sponsors a program, executed by Los Alamos National Laboratory, to recover radioisotopes used by industry and academia and no longer needed. Called the "Offsite Source Recovery Program (OSRP), it has recovered

  3. Recovering Radioactive Materials with OSRP team

    ScienceCinema

    None

    2016-07-12

    The National Nuclear Security Administration sponsors a program, executed by Los Alamos National Laboratory, to recover radioisotopes used by industry and academia and no longer needed. Called the "Offsite Source Recovery Program (OSRP), it has recovered

  4. Ribavirin Prophylaxis and Therapy for Experimental Argentine Hemorrhagic Fever

    DTIC Science & Technology

    1988-09-01

    cessation, values began to patients with Lassa fever in Sierra Leone. where mortality increase, progressively returning toward the base line. The reductions...similar to Bo- Virus isolation and serology. Virus was recovered from all livian hemorrhagic fever than to Lassa fever in humans (18). placebo-treated...clinical re- pti- d for use in Lassa fever patient%. Trisicol. Appi. Phama- spofl5c. J Infect. Dis. 152:218-221. cl 41519 16. McKee, K. T., Jr., IL. G

  5. Assessing resilience of western rangelands to transportation-related land-use change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The amount and extent of transportation related activity in western rangelands has rapidly increased in recent decades. This increase is due to a variety of factors including oil and gas development, recreational activities, and ex-urban development. In addition to areas directly impacted by infrast...

  6. Germination and seedling emergence of three western North American rangeland legumes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Few seed sources of North American forbs are available for revegetation/restoration of degraded western rangelands adapted to precipitation zones less than 300 mm, and those that are available are mainly wildland-collected. The amount of time and resources necessary to make wildland collections in ...

  7. 75 FR 18144 - Kemmerer Ranger District, Bridger-Teton National Forest, Wyoming Kemmerer Grazing and Rangeland...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-09

    ... Rangeland Vegetation Management Project AGENCY: Forest Service, USDA. ACTION: Notice of intent to prepare an... management of grazing allotments within the project area. News releases were also made to encourage public... the addition of the Porcupine allotment to the proposed project area. The project area encompasses...

  8. Vulnerabilities and adaptive capacities of southwest rangeland livestock production to climate change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rangeland livestock industry across the southwestern US (California, Nevada, Arizona, Utah and New Mexico) consists of highly diverse production operations in these arid and semi-arid environments with low primary productivity. The vulnerabilities of this industry with projected increasing arid...

  9. Perennial grass dominance: creating a resilient plant community in an exotic annual grass invaded rangeland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Millions of hectares of western rangelands have been invaded by the exotic and invasive annual grass, cheatgrass (Bromus tectorum). Cheatgrass provides a fine-textured, early maturing fuel that has increased the chance, rate, spread and season of wildfire to public and private lands throughout the ...

  10. Contrasting watershed-scale trends in runoff and sediment yield complicate rangeland water resources planning

    NASA Astrophysics Data System (ADS)

    Berg, Matthew D.; Marcantonio, Franco; Allison, Mead A.; McAlister, Jason; Wilcox, Bradford P.; Fox, William E.

    2016-06-01

    Rangelands cover a large portion of the earth's land surface and are undergoing dramatic landscape changes. At the same time, these ecosystems face increasing expectations to meet growing water supply needs. To address major gaps in our understanding of rangeland hydrologic function, we investigated historical watershed-scale runoff and sediment yield in a dynamic landscape in central Texas, USA. We quantified the relationship between precipitation and runoff and analyzed reservoir sediment cores dated using cesium-137 and lead-210 radioisotopes. Local rainfall and streamflow showed no directional trend over a period of 85 years, resulting in a rainfall-runoff ratio that has been resilient to watershed changes. Reservoir sedimentation rates generally were higher before 1963, but have been much lower and very stable since that time. Our findings suggest that (1) rangeland water yields may be stable over long periods despite dramatic landscape changes while (2) these same landscape changes influence sediment yields that impact downstream reservoir storage. Relying on rangelands to meet water needs demands an understanding of how these dynamic landscapes function and a quantification of the physical processes at work.

  11. Effects of Grazing Pressure on Efficiency of Grazing on North American Great Plains Rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Robust prediction models describing vegetation and animal responses to stocking rate in North American Great Plains rangelands are lacking as across site comparisons are limited by different qualitative designations of light, moderate and heavy stocking. Comparisons of stocking rates across sites ca...

  12. Deriving empirical benchmarks from existing monitoring datasets for rangeland adaptive management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Under adaptive management, goals and decisions for managing rangeland resources are shaped by requirements like the Bureau of Land Management’s (BLM’s) Land Health Standards, which specify desired conditions. Without formalized, quantitative benchmarks for triggering management actions, adaptive man...

  13. Social-biophysical feedbacks and land change in an arid rangeland region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies of human-dominated ecosystems have traditionally externalized human agents and their behavior. Rangelands of the southwestern U.S. are no exception: in spite of century-long studies of vegetation change, the specific role of human decisions and their feedbacks with land condition are unknown...

  14. Evidence targeted grazing benefits to invaded rangelands can increase over extended time frames

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prescribed grazing uses livestock to address rangeland management issues such as woody plant encroachment, accumulations of flammable biomass and exotic weed invasions. Invasive weed responses to prescribed grazing have proven variable. For instance, a given livestock species can sharply reduce ab...

  15. Integrating rangeland and pastureland assessment methods into a national grazingland assessment approach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grazingland resource allocation and decision making at the national scale need to be based on comparable metrics. However, in the USA, rangelands and pasturelands have traditionally been assessed using different methods and indicators. These differences in assessment methods limit the ability to con...

  16. Forage and weather influcence day versus nighttime cow behavior and calf weaning weights on rangeland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We determined the effects of two forage allowance levels (LOW vs. HIGH) and weather conditions on day- and nighttime movement patterns of young rangeland-raised cows. We also investigated whether calf weaning weights (WW, n = 42) were significantly related to their dams' post-calving movement patter...

  17. Lessons from community-based payment for ecosystem service schemes: from forests to rangelands

    PubMed Central

    Dougill, Andrew J.; Stringer, Lindsay C.; Leventon, Julia; Riddell, Mike; Rueff, Henri; Spracklen, Dominick V.; Butt, Edward

    2012-01-01

    Climate finance investments and international policy are driving new community-based projects incorporating payments for ecosystem services (PES) to simultaneously store carbon and generate livelihood benefits. Most community-based PES (CB-PES) research focuses on forest areas. Rangelands, which store globally significant quantities of carbon and support many of the world's poor, have seen little CB-PES research attention, despite benefitting from several decades of community-based natural resource management (CBNRM) projects. Lessons from CBNRM suggest institutional considerations are vital in underpinning the design and implementation of successful community projects. This study uses documentary analysis to explore the institutional characteristics of three African community-based forest projects that seek to deliver carbon-storage and poverty-reduction benefits. Strong existing local institutions, clear land tenure, community control over land management decision-making and up-front, flexible payment schemes are found to be vital. Additionally, we undertake a global review of rangeland CBNRM literature and identify that alongside the lessons learned from forest projects, rangeland CB-PES project design requires specific consideration of project boundaries, benefit distribution, capacity building for community monitoring of carbon storage together with awareness-raising using decision-support tools to display the benefits of carbon-friendly land management. We highlight that institutional analyses must be undertaken alongside improved scientific studies of the carbon cycle to enable links to payment schemes, and for them to contribute to poverty alleviation in rangelands. PMID:23045714

  18. Developing soil erodibility prediction equations for the Rangeland Hydrology and Erosion Model (RHEM)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil erodibility is a key factor for estimating soil erosion using physically based models. In this study, a new parameterization approach for estimating erodibility was developed for the Rangeland Hydrology and Erosion Model (RHEM). The approach uses empirical equations that were developed by apply...

  19. Rangeland remote sensing applications with unmanned aerial systems (UAS) in the national airspace: challenges and experiences

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent years, civilian applications of unmanned aerial systems (UAS) have increased considerably due to their greater availability and the miniaturization of sensors, GPS, inertial measurement units, and other hardware. UAS are well suited for rangeland remote sensing applications, because of the...

  20. Unmanned aircraft missions for rangeland remote sensing applications in the US National Airspace

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent years, civilian applications of unmanned aerial systems (UAS) have increased considerably due to their greater availability and the miniaturization of sensors, GPS, inertial measurement units, and other hardware. UAS are well suited for rangeland remote sensing applications, because of the...

  1. Hydrologic and erosional impacts associated with an increased role of wildland fire on western rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Landscape plant community transitions across the Great Basin and Intermountain West have altered fire regimes and present large-scale consequences relative to rangeland hydrology. Extensive conversion of Great Basin shrub steppe to annual grasslands has increased fuel continuity and the frequency, ...

  2. BIRD SPECIES ASSEMBLAGES AS INDICATORS OF BIOLOGICAL INTEGRITY IN GREAT BASIN RANGELAND

    EPA Science Inventory

    The study evaluates the potential for bird species assemblages to serve as indicators of biological integrity of rangelands in the Great Basin in much the same way that fish and invertebrate assemblages have been used as indicators in aquatic environments. Our approach was to ide...

  3. Mitigation of larkspur poisoning on rangelands through the selection of cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toxic larkspur (Delphinium species) in the western United States cause large economic losses from cattle deaths, increased management costs, and reduced utilization of pastures and rangelands. Peak larkspur toxicity coincides with maximum productivity of the range, which reduces the profitability of...

  4. Rangeland assessment and monitoring methods guide - an interactive tool for selecting methods for assessment and monitoring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A common concern expressed by land managers and biologists is that they do not know enough about the strengths and weaknesses of different field and remote-sensing methods for rangeland assessment and monitoring. The Methods Guide is a web-based tool and resource that provides researchers and manage...

  5. USDA-ARS Poisonous Plant Research Laboratory: History and current research on western North American rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Poisonous plants on western North American rangelands have historically been troublesome to livestock producers. Research on toxic plants was initiated by U.S. Department of Agriculture in the late 1890’s to solve problems for the livestock industry. The USDA-ARS Poisonous Plant Research Laborator...

  6. Introduction to the USDA-Agricultural Research Service Poisonous Plant Research Laboratory Special Rangelands Issue

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA-ARS Poisonous Plant Research Labortory (PPRL) in Logan, UT will sponsor an edition of the magazine Rangelands. This paper provides a brief history and overview of the PPRL, mission statement, research objectives by CRIS, and the disciplines involved in the research....

  7. Ecosystem water availability in juniper versus sagebrush snow-dominated rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Western Juniper (J. occidentalis Hook.) now dominates over 3.6 million ha of rangeland in the Intermountain Western US. Critical ecological relationships among snow distribution, water budgets, plant community transitions, and habitat requirements for wildlife, such as sage grouse, remain poorly und...

  8. Launching the Counterattack: Interdisciplinary Deployment of Functional Traits to Repair Damaged Intermountain Rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ecologists worldwide recognize that the novel ecosystems of the future will display radically different structure and function from ecosystems that have dominated the study of ecology up until the prsent time. Because of both abiotic and biotic obstacles, rangelands dominated by invasive plants are...

  9. Lessons from community-based payment for ecosystem service schemes: from forests to rangelands.

    PubMed

    Dougill, Andrew J; Stringer, Lindsay C; Leventon, Julia; Riddell, Mike; Rueff, Henri; Spracklen, Dominick V; Butt, Edward

    2012-11-19

    Climate finance investments and international policy are driving new community-based projects incorporating payments for ecosystem services (PES) to simultaneously store carbon and generate livelihood benefits. Most community-based PES (CB-PES) research focuses on forest areas. Rangelands, which store globally significant quantities of carbon and support many of the world's poor, have seen little CB-PES research attention, despite benefitting from several decades of community-based natural resource management (CBNRM) projects. Lessons from CBNRM suggest institutional considerations are vital in underpinning the design and implementation of successful community projects. This study uses documentary analysis to explore the institutional characteristics of three African community-based forest projects that seek to deliver carbon-storage and poverty-reduction benefits. Strong existing local institutions, clear land tenure, community control over land management decision-making and up-front, flexible payment schemes are found to be vital. Additionally, we undertake a global review of rangeland CBNRM literature and identify that alongside the lessons learned from forest projects, rangeland CB-PES project design requires specific consideration of project boundaries, benefit distribution, capacity building for community monitoring of carbon storage together with awareness-raising using decision-support tools to display the benefits of carbon-friendly land management. We highlight that institutional analyses must be undertaken alongside improved scientific studies of the carbon cycle to enable links to payment schemes, and for them to contribute to poverty alleviation in rangelands.

  10. Weight gain and behavior of Raramuri Criollo versus crossbred steers developed on Chihuahuan Desert rangeland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ranchers that raise Raramuri Criollo (RC) cattle must overcome the challenge of lack of markets for weaned calves. Growing and finishing RC or RC-crossbred steers on rangeland pastures is increasingly common; however, no data exist on their weight gains or grazing behavior. We tracked the weight a...

  11. A review of concentrated flow erosion processes on rangelands: fundamental understanding and knowledge gaps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Concentrated flow erosion processes are distinguished from splash and sheetflow processes in their enhanced ability to mobilize and transport large amounts of soil, water and dissolved elements. On rangelands, soil, nutrients and water are scarce and only narrow margins of resource losses are tolera...

  12. Assessing impacts of fire and post-fire mitigation on runoff and erosion from rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wildfires are a natural component of rangeland ecosystems, but fires can pose hydrologic hazards for ecological resources, infrastructure, property, and human life. There has been considerable research conducted on the effects of fire on hydrologic processes and erosion on shrublands and woodlands....

  13. Semiarid rangeland is resilient to summer fire and post-fire grazing utilization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    1. Most wildfires occur during summer in the northern hemisphere, the area burned annually is increasing, and fire effects during this season are least understood. Livestock grazing is a primary use of rangelands affected by wildfire, but post-fire grazing management is not well-supported with dat...

  14. Mimosa tenuiflora as a Cause of Malformations in Ruminants in the Northeastern Brazilian Semiarid Rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Craniofacial anomalies, eye malformations, and permanent flexures of the forelimbs are common malformations seen in ruminants grazing semiarid rangelands of Northeastern Brazil. To investigate the cause of these malformations, we fed 2 suspected plants, Mimosa tenuiflora or Prosopis juliflora, to gr...

  15. Improving restoration of exotic annual grass-invaded rangelands through activated carbon seed enhancement technologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cost-efficient strategies for revegetating annual grass-infested rangelands are limited. Restoration efforts typically comprise a combination of pre-emergent herbicide treatments and seeding to restore desired plant materials. However, practitioners struggle with applying herbicide at rates sufficie...

  16. The conservation-production interface in rangelands: Acknowledging tradeoffs and moving towards win-win solutions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Provision of wildlife habitat in rangelands, particularly for birds of conservation concern, is increasingly recognized as an important ecosystem service. Accommodating human use is also a key component of ecosystem management. Most remaining grassland bird habitat in the western Great Plains is pri...

  17. Movement and spatial proximity patterns of rangeland-raised Raramuri Criollo cow-calf pairs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to compare movement patterns of nursing vs. nonnursing mature cows and to characterize cow-calf proximity patterns in two herds of Raramuri Criollo cattle. Herds grazed rangeland pastures in southern New Mexico (4355 ha) and west-central Chihuahua, Mexico (633 ha)'' A...

  18. Ground Based Reflectance Measurements of Arid Rangeland Vegetation Communities of the Southwestern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 1997 a research program began using an Analytical Spectral Device (ASD-FR) spectroradiometer to collect ground based in situ radiance/reflectance measurements from vegetation communities typical of semiarid/arid rangelands of southwestern United States. Measurements were made after the spring (Ap...

  19. Reflectance Measurements of Vegetation Communities in Arid Rangelands of New Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA ARS Jornada Experimental Range (Jornada) in southern New Mexico and the Sevilleta National Wildlife Refuge (Sevilleta) in Central New Mexico are Long Term Ecological Research (LTER) sites that provide unique opportunities to study changing rangeland communities using remote sensing techniqu...

  20. The importance of persistent monitoring of great basin rangeland rehabilitation efforts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It has long been acknowledged the drastic change in fire cycles of the Great Basin rangelands due to cheatgrass (Bromus tectorum) invasion (Billings 1952, Young and Evans 1974, Wright 1980). An annual grass fire cycle now exists with return intervals less than 5 years compared to historical 60 to110...

  1. Feeding goats on scrubby Mexican rangeland and pasteurization: influences on milk and artisan cheese quality.

    PubMed

    Hilario, Mario Cuchillo; Puga, Claudia Delgadillo; Wrage, Nicole; Pérez-Gil R, Fernando

    2010-08-01

    The objective of this study was to evaluate the effect of foraging on local scrubby rangeland versus stable feeding with high-protein concentrate as well as the compulsory pasteurization process on goats' milk and artisan soft cheese quality in terms of chemical composition and fatty acid profile. The results indicated that there were no significant differences in the energy, fat, or ash content of milk and cheese due to feeding; however, a significant influence of feeding on cheese protein and fatty acids in both milk and cheese was detected. Feeding on scrubby rangeland tended to increase the amounts of major polyunsaturated fatty acids in milk and cheese from goats. Pasteurization, which is mandatory in Mexico, did not alter the fatty acid concentrations in milk or cheese. Small goat-keepers using rangeland resources might claim better economical returns for products recognized as healthier. Further investigations to assure ecosystem sustainability of shrubby rangeland joined with economical evaluations and best animal management to avoid deleterious effects are recommended.

  2. Tipping points in rangeland social-ecological systems of the Southwest US: Past and present

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background/Question/Methods: The advent of social-ecological system perspectives has led to new questions about the causes and consequences of global change. Nearly all research in rangeland ecosystems of the U.S. has focused on transitions in vegetation (such as grasslands to shrublands) casting h...

  3. Two new mobile apps for rangeland inventory and monitoring by landowners and land managers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland inventory and monitoring have been transformed during the past 10 years by a number of major innovations. This paper reviews the status of two new mobile apps (LandInfo and LandCover) that are part of a larger “Land-Potential Knowledge System” (LandPKS) that is being developed to capitaliz...

  4. Controls over the strength and timing of fire-grazer interactions in semiarid rangeland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The degree to which large herbivores select and forage within recently burned areas is a key driver of vegetation heterogeneity in rangeland ecosystems. Yet few studies have carefully quantified the strength and timing of herbivore selection for burns or how selection strength varies among ecosystem...

  5. Assessing and managing rangeland and enterprise resilience using the integrated grazingland assessment method

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resilient shifts into undesirable natural States (as described in State-and-Transition models) opens up opportunities for using agronomic practices to maintain the function of rangeland ecosystems as well as maintaining the provisioning of goods and services from these areas. There is a need for a m...

  6. Estimating overnight weight loss of corralled yearling steers in semiarid rangeland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Free-ranging livestock grazing native vegetation on rangelands are frequently gathered and confined overnight in a corral (sensu drylot) prior to weighing to determine periodic weight gains for grazing studies. Quantification of this overnight percent shrink across the grazing season could provide t...

  7. US forest service technical cooperation visit Badia Rangeland and irrigation analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A US Forest Service (USFS) team comprised of a rangeland management advisor, a dryland water resource, and irrigation specialist, and a Middle East program specialist visited Jordan to provide technical assistance to the Ministry of Agriculture-Water Harvesting Directorate (MoA) and the Hashemite Fu...

  8. The potential value of Festuca valesiaca for use on Great Basin Rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fine-leaved Festuca valesiaca possesses varied abiotic tolerances and is widely distributed on Asian rangelands. However, its performance in the western United States has not been investigated. Therefore, F. valesiaca accessions were evaluated for performance and their relatedness to species in th...

  9. Vulnerabilities of Southwestern U.S. rangeland-based animal agriculture to climate change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Southwestern US is a 5-state region that has supported animal agriculture since the late 16th Century when European settlers crossed the Rio Grande into present day west Texas and southern New Mexico with herds of cattle, sheep, goats and horses. For the past 400 years the rangeland livestock i...

  10. Disaggregation of Soil Map Units for Improved Ecological Site Mapping in Rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland soils are often mapped with soil map units consisting of associations, complexes, and undifferentiated groups composed of varied soil components. Because different components may be related to different ecological sites, the unmapped heterogeneity within map units limits the potential uses...

  11. Disaggregation of soil map units for improved ecological site mapping in rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland soils are often mapped with soil map units consisting of associations, complexes, and undifferentiated groups composed of varied soil components. Because different components may be related to different ecological sites, the unmapped heterogeneity within map units limits the potential uses...

  12. 75 FR 10754 - Humboldt-Toiyabe National Forests; Santa Rosa Ranger District; Martin Basin Rangeland Management...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-09

    ... authorize grazing on three of the allotments in the Project Area (the Buffalo, Granite Creek, and Rebel... grazing management. 2. No Grazing Alternative: Eliminate grazing in the Buffalo, Granite Creek, and Rebel... the Buffalo, Granite Creek, and Rebel Creek Allotments in the Martin Basin Rangeland Project area....

  13. SOIL MICROARTHROPODS AS INDICATORS OF EXPOSURE TO ENVIRONMENTAL STRESS IN CHIHUAHUAN DESERT RANGELANDS.

    EPA Science Inventory

    We studied soil microarthropod communities along livestock grazing disturbance gradients, inside and outside grazing exclosures, and on areas subjected to restoration efforts(herbicide and bulldozing)in order to test the suitability of mites as indicators of rangeland soil qualit...

  14. Application of a rangeland soil erosion model using NRI data in southeastern Arizona

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangelands comprise a large portion of the western United States. They are important for providing ecosystem services such as sources of clean water and air, wildlife habitat, ecosystem biodiversity, recreation, and aesthetics. The National Resources Inventory (NRI) is a primary data source for on-...

  15. Orthorectification, mosaicking, and analysis of sub-decimeter resolution UAV imagery for rangeland monitoring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned aerial vehicles (UAVs) offer an attractive platform for acquiring imagery for rangeland monitoring. UAVs can be deployed quickly and repeatedly, and they can obtain sub-decimeter resolution imagery at lower image acquisition costs than with piloted aircraft. Low flying heights result in ima...

  16. Acquisition, orthorectification, and object-based classification of unmanned aerial vehicle (UAV) imagery for rangeland monitoring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper, we examine the potential of using a small unmanned aerial vehicle (UAV) for rangeland inventory, assessment and monitoring. Imagery with 8-cm resolution was acquired over 290 ha in southwestern Idaho. We developed a semi-automated orthorectification procedure suitable for handling lar...

  17. Incorporation of texture, intensity, hue, and saturation for rangeland monitoring with unmanned aircraft imagery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aerial photography acquired with unmanned aerial vehicles (UAVs) has great potential for incorporation into rangeland health monitoring protocols, and object-based image analysis is well suited for this hyperspatial imagery. A major drawback, however, is the low spectral resolution of the imagery, b...

  18. Unmanned aerial vehicles for hyperspatial remote sensing of rangelands: object-based classification and field validation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    UAVs are ideally suited for monitoring and assessing vegetation conditions in remote rangelands due to the relatively low operating costs, ability for fast deployment, and greater flexibility than piloted aircraft. The likelihood of obtaining FAA permission for operating a UAV is also greater in rem...

  19. Multiscale variability of soil aggregate stability: implications for rangeland hydrology and erosion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conservation of soil and water resources in rangelands is a crucial step in stopping desertification processes. The formation of water-stable soil aggregates reduces soil erodibility and can increase infiltration capacity in many soils. Soil aggregate stability is highly variable at scales ranging f...

  20. Use of RHEM to assess runoff and erosion following disturbance on rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Landscape disturbance such as fire or woody plant encroachment on rangelands can have major impacts on the hydrological and erosion responses. As canopy and ground cover are reduced, soil sediments become available and can be detached by rain splash and overland flow. Disturbance can also increase t...

  1. Plant and soil consequences of shrub management in a big sagebrush-dominated rangeland ecosystem

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil organic carbon (SOC) responses to shrub management in western US rangelands, especially those dominated by Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young) in low rainfall areas (<300 mm), remains a major knowledge gap. We sampled vegetation and soils in 2009 ...

  2. Salinity mobilization and transport from rangelands: assessment, recommendations, and knowledge gaps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of the salinity project is to improve the understanding of sources and transport mechanisms in rangeland catchments that deliver dissolved solids (salts) to streams within the Upper Colorado River Basin (UCRB) through a review of relevant literature on what is known about the impact of r...

  3. Spatially explicit rangeland erosion monitoring using high-resolution digital aerial imagery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nearly all of the ecosystem services supported by rangelands, including production of livestock forage, carbon sequestration, and provisioning of clean water, are negatively impacted by soil erosion. Accordingly, monitoring the severity, spatial extent, and rate of soil erosion is essential for long...

  4. Prediction of senescent rangeland canopy structural attributes with airborne hyperspectral imagery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Canopy structural and chemical data are needed for senescent, mixed-grass prairie landscapes in autumn, yet models driven by image data are lacking for rangelands dominated by non-photosynthetically active vegetation (NPV). Here, we report how aerial hyperspectral imagery might be modeled to predic...

  5. Climate-change adaptation on rangelands: Linking regional exposure with diverse adaptive capacity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ecological consequences of climate change are anticipated to vary greatly throughout North American rangelands. Projections are for warming and drying in the southern plains, southwest and northern Mexico; warmer, drier summers, with reduced winter snowpack in northwest; and warmer, wetter condi...

  6. Analytical approaches to quality assurance and quality control in rangeland monitoring data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Producing quality data to support land management decisions is the goal of every rangeland monitoring program. However, the results of quality assurance (QA) and quality control (QC) efforts to improve data quality are rarely reported. The purpose of QA and QC is to prevent and describe non-sampling...

  7. Modeling the effects on water erosion processes of rangeland conservation practices in the Great Basin region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Rangeland Hydrology and Erosion Model (RHEM) is an event-based model developed by the USDA-ARS. The model has been developed to estimates runoff, erosion, and sediment delivery rates and volumes at the spatial scale of the hillslope and the temporal scale of a single rainfall event. It represent...

  8. A strategy for rangeland management based on best available knowledge and information

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Changes to rangeland systems are happening at spatial and temporal scales beyond the capability of our current knowledge and information systems. In this paper we look at how Web 2.0 tools such as wikis and crowd-sourcing and new technologies including mobile devices and massive online databases are...

  9. Insight into sediment transport processes on saline rangeland hillslopes using three-dimensional soil microtoprgraphy changes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hillslope runoff and soil erosion processes play a vital role on rangeland ecosystem sustainability due to their control on resource mobility but they also have significant implications in off-site resource transport. In general, physically-based soil erosion models such as RHEM divide erosion and ...

  10. An assessment of behavioral syndromes in rangeland-raised beef cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Individuals in most animal groups exhibit consistent behavioural differences across situations or over time known as behavioural syndromes. We conducted a study with a herd of young rangeland-raised cows to determine whether animals exhibited consistent differences in foraging behaviours across cont...

  11. Argentine ant invasion associated with loblolly pines in the southeastern United States: minimal impacts but seasonally sustained.

    PubMed

    Rowles, Alexei D; Silverman, Jules

    2010-08-01

    Invasive ants are notorious for directly displacing native ant species. Although such impacts are associated with Argentine ant invasions (Linepithema humile) worldwide, impacts within natural habitat are less widely reported, particularly those affecting arboreal ant communities. Argentine ants were detected in North Carolina mixed pine-hardwood forest for the first time but were localized on and around loblolly pines (Pinus taeda), probably because of association with honeydew-producing Hemiptera. We explored the potential impacts of L. humile on arboreal and ground-foraging native ant species by comparing interspersed loblolly pines invaded and uninvaded by Argentine ants. Impacts on native ants were assessed monthly over 1 yr by counting ants in foraging trails on pine trunks and in surrounding plots using a concentric arrangement of pitfall traps at 1, 2, and 3 m from the base of each tree. Of floristics and habitat variables, higher soil moisture in invaded plots was the only difference between plot types, increasing confidence that any ant community differences were caused by Argentine ants. Overall patterns of impact were weak. Composition differed significantly between Argentine ant invaded and uninvaded trunks and pitfalls but was driven only by the presence of Argentine ants rather than any resulting compositional change in native ant species. Native ant abundance and richness were similarly unaffected by L. humile. However, the abundance of individual ant species was more variable. Although numbers of the arboreal Crematogaster ashmeadi (Myrmicinae) declined on and around invaded pines, epigeic Aphaenogaster rudis (Myrmicinae) remained the most abundant species in all plots. Argentine ant densities peaked in late summer and fall, therefore overlapping with most native ants. Unexpected was their continued presence during even the coldest months. We provide evidence that Argentine ants can invade and persist in native North Carolina forests, probably

  12. Long-term field trial to control the invasive Argentine ant (Hymenoptera: Formicidae) with synthetic trail pheromone.

    PubMed

    Nishisue, K; Sunamura, E; Tanaka, Y; Sakamoto, H; Suzuki, S; Fukumoto, T; Terayama, M; Tatsuki, S

    2010-10-01

    Previous short-term experiments showed that trail following behavior of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae), can be disrupted by a high concentration of synthetic trail pheromone component (Z)-9-hexadecenal. In this study, a long-term field trial was conducted in 100-m2 plots of house gardens in an urban area of Japan to see whether the control effect on Argentine ants can be obtained by permeating synthetic trail pheromone from dispensers. The dispensers were placed in the experimental plots during the ant's active season (April-November) for 2 yr with monthly renewal. To estimate Argentine ant population density, foraging activity of Argentine ants in the study plots was monitored by monthly bait surveys. Throughout the study period, Argentine ant foraging activity was suppressed in the presence of the dispensers, presumably via trail forming inhibition. In contrast, the level of foraging activity was not different between treatment and no-treatment plots when the dispensers were temporarily removed, suggesting that treatment with pheromone dispensers did not suppress Argentine ant density in the treatment plots. Population decline may be expected with larger-scale treatment that covers a significant portion of the ant colony or with improvement in the potency of the disruptant.

  13. Is the Invasive Species Listronotus bonariensis (Kuschel) (Coleoptera: Curculionidae) (Argentine Stem Weevil) a Threat to New Zealand Natural Grassland Ecosystems?

    PubMed Central

    Barratt, Barbara I. P.; Barton, Diane M.; Philip, Bruce A.; Ferguson, Colin M.; Goldson, Stephen L.

    2016-01-01

    Listronotus bonariensis (Argentine stem weevil) is a stem-boring weevil that has become a major pasture pest in New Zealand, and cool climate turf grass in Australia. This species is also frequently found in native tussock grassland in New Zealand. Laboratory and field trials were established to determine the risk posed to both seedlings and established plants of three native grass species compared to what happens with a common host of this species, hybrid ryegrass (L. perenne X L. multiflorum). Adult weevil feeding damage scores were higher on Poa colensoi and Festuca novae-zelandiae than Chionochloa rigida. Oviposition was lower on P. colensoi than hybrid ryegrass, and no eggs were laid on F. novae-zelandiae. In field trials using the same four species established as spaced plants L. bonariensis laid more eggs per tiller in ryegrass in a low altitude pasture site than in ryegrass in a higher altitude site. No eggs were found on the three native grass species at the tussock sites, and only low numbers were found on other grasses at the low altitude pasture site. Despite this, numbers of adult weevils were extracted from the plants in the field trials. These may have comprised survivors of the original weevils added to the plants, together with new generation weevils that had emerged during the experiment. Irrespective, higher numbers were recovered from the tussock site plants than from those from the pasture site. It was concluded that L. bonariensis is likely to have little overall impact, but a greater impact on native grass seedling survival than on established plants. PMID:27507979

  14. Is the Invasive Species Listronotus bonariensis (Kuschel) (Coleoptera: Curculionidae) (Argentine Stem Weevil) a Threat to New Zealand Natural Grassland Ecosystems?

    PubMed

    Barratt, Barbara I P; Barton, Diane M; Philip, Bruce A; Ferguson, Colin M; Goldson, Stephen L

    2016-01-01

    Listronotus bonariensis (Argentine stem weevil) is a stem-boring weevil that has become a major pasture pest in New Zealand, and cool climate turf grass in Australia. This species is also frequently found in native tussock grassland in New Zealand. Laboratory and field trials were established to determine the risk posed to both seedlings and established plants of three native grass species compared to what happens with a common host of this species, hybrid ryegrass (L. perenne X L. multiflorum). Adult weevil feeding damage scores were higher on Poa colensoi and Festuca novae-zelandiae than Chionochloa rigida. Oviposition was lower on P. colensoi than hybrid ryegrass, and no eggs were laid on F. novae-zelandiae. In field trials using the same four species established as spaced plants L. bonariensis laid more eggs per tiller in ryegrass in a low altitude pasture site than in ryegrass in a higher altitude site. No eggs were found on the three native grass species at the tussock sites, and only low numbers were found on other grasses at the low altitude pasture site. Despite this, numbers of adult weevils were extracted from the plants in the field trials. These may have comprised survivors of the original weevils added to the plants, together with new generation weevils that had emerged during the experiment. Irrespective, higher numbers were recovered from the tussock site plants than from those from the pasture site. It was concluded that L. bonariensis is likely to have little overall impact, but a greater impact on native grass seedling survival than on established plants.

  15. Effects of aromatic cedar mulch on the Argentine ant and the odorous house ant (Hymenoptera: Formicidae).

    PubMed

    Meissner, H E; Silverman, J

    2001-12-01

    In laboratory studies, the Argentine ant, Linepithema humile (Mayr), and the odorous house ant, Tapinoma sessile (Say), avoided aromatic cedar mulch as a nesting substrate. Both ant species were killed when confined with fresh aromatic cedar mulch in sealed containers. However, when confined with cedar mulch that had been aged outdoors for up to 140 d, mortality of L. humile was complete regardless of mulch age, whereas T. sessile mortality declined significantly over the mulch-aging period. Argentine ant susceptibility to aromatic cedar mulch was also greater than that of the odorous house ant when colonies were restricted to mulch in open trays. In addition, commercial aromatic cedar oil was lethal to both ant species. Our results suggest that aromatic cedar mulch may serve as an effective component of a comprehensive urban ant management program.

  16. Variation of terpenes in milk and cultured cream from Norwegian alpine rangeland-fed and in-door fed cows.

    PubMed

    Borge, Grethe Iren A; Sandberg, Ellen; Øyaas, Jorun; Abrahamsen, Roger K

    2016-05-15

    The terpene content of milk and cream made from milk obtained from cows fed indoors, and by early or late grazing, in alpine rangeland farms in Norway, were analysed for three consecutive years. The main terpenes identified and semi-quantified were the monoterpenes β-pinene, α-pinene, α-thujene, camphene, sabinene, δ-3-carene, d-limonene, γ-terpinene, camphor, β-citronellene, and the sesquiterpene β-caryophyllene. The average total terpene content increased five times during the alpine rangeland feeding period. The terpenes α-thujene, sabinene, γ-terpinene and β-citronellene were only detected in milk and cultured cream from the alpine rangeland feeding period and not in samples from the indoors feeding period. These four terpenes could be used, as indicators, to show that milk and cultured cream originate from the alpine rangeland feeding period. The terpenes did not influence the sensorial quality of the milk or the cultured cream.

  17. Draft Genome Sequences of Four Enterococcus faecium Strains Isolated from Argentine Cheese.

    PubMed

    Martino, Gabriela P; Quintana, Ingrid M; Espariz, Martín; Blancato, Victor S; Gallina Nizo, Gabriel; Esteban, Luis; Magni, Christian

    2016-02-04

    We report the draft genome sequences of four Enterococcus faecium strains isolated from Argentine regional cheeses. These strains were selected based on their technological properties, i.e., their ability to produce aroma compounds (diacetyl, acetoin, and 2,3-butanediol) from citrate. The goal of our study is to provide further genetic evidence for the rational selection of enterococci strains based on their pheno- and genotype in order to be used in cheese production.

  18. Draft Genome Sequences of Four Enterococcus faecium Strains Isolated from Argentine Cheese

    PubMed Central

    Martino, Gabriela P.; Quintana, Ingrid M.; Espariz, Martín; Blancato, Victor S.; Gallina Nizo, Gabriel; Esteban, Luis

    2016-01-01

    We report the draft genome sequences of four Enterococcus faecium strains isolated from Argentine regional cheeses. These strains were selected based on their technological properties, i.e., their ability to produce aroma compounds (diacetyl, acetoin, and 2,3-butanediol) from citrate. The goal of our study is to provide further genetic evidence for the rational selection of enterococci strains based on their pheno- and genotype in order to be used in cheese production. PMID:26847907

  19. Vitrification Demonstration with Argentine Ion Exchange Material in the Stir-Melter

    SciTech Connect

    Cicero-Herman, C.A.

    2002-06-28

    The Savannah River Technology Center (SRTC) is investigating the viability of vitrification treatment of Argentine ion exchange material as part of a Department of Energy (DOE) - Office of Science and Technology Development Task Plan. Bench-scale studies were performed by the SRTC to define the necessary vitrification process for this material. However, the process had to be demonstrated in a melter system before vitrification could be considered a viable treatment option.

  20. Survey of Argentine Health Researchers on the Use of Evidence in Policymaking

    PubMed Central

    Corluka, Adrijana; Hyder, Adnan A.; Segura, Elsa; Winch, Peter; McLean, Robert K. D.

    2015-01-01

    Objective In this study, Argentine health researchers were surveyed regarding their perceptions of facilitators and barriers to evidence-based policymaking in Argentina, as well as their publication activities, and research environment satisfaction. Methods A self-administered online survey was sent to health researchers in Argentina. The survey questions were based on a preceding qualitative study of Argentine health researchers, as well as the scientific literature. Results Of the 647 researchers that were reached, 226 accessed the survey, for a response rate of 34.9%. Over 80% of researchers surveyed had never been involved in or contributed to decision-making, while over 90% of researchers indicated they would like to be involved in the decision-making process. Decision-maker self-interest was perceived to be the driving factor in the development of health and healthcare policies. Research conducted by a research leader was seen to be the most influential factor in influencing health policy, followed by policy relevance of the research. With respect to their occupational environment, researchers rated highest and most favourably the opportunities available to present, discuss and publish research results and their ability to further their education and training. Argentine researchers surveyed demonstrated a strong interest and willingness to contribute their work and expertise to inform Argentine health policy development. Conclusion Despite Argentina’s long scientific tradition, there are relatively few institutionalized linkages between health research results and health policymaking. Based on the results of this study, the disconnect between political decision-making and the health research system, coupled with fewer opportunities for formalized or informal researcher/decision-maker interaction, contribute to the challenges in evidence informing health policymaking in Argentina. Improving personal contact and the building of relationships between

  1. Brazilian-Argentine Relations in the 1980s: from Wary Rivalry toward Friendly Competition

    DTIC Science & Technology

    1985-03-01

    premises is that attention should be drawn from territorial disputes to developmental issues. Brazil’s interest will move into cautious, modest, and almost...contrasted with a national defense concept. 3. Settlement of Argentine territorial disputes with Chile and at least attenuation of the Falklands...betterment in political relations and the shift from a territorial defense preoccupation toward a largely socio-economic concept of national security

  2. Assessment of the Applicability of Total Quality Leadership into the Argentine Army.

    DTIC Science & Technology

    1995-03-01

    vocabulary. 2. The Department of Navy (DON) and Quality Most of the information of this section was derived from Suarez , J.G., Three Experts on Quality...examples in the Argentine Army of leaders who exemplify driving out fear. Col Miguel Enrique Chichizola was one example. He was in charge of the 601...Nonprofit Organization. San Francisco: Jossey-Bass Publishers. 7. Suarez , J.G. 1992. Three Experts on Quality Management: Philip B. Crosby. W.Edwards

  3. Effect of aromatic cedar mulch on Argentine ant (Hymenoptera: Formicidae) foraging activity and nest establishment.

    PubMed

    Meissner, Heike E; Silverman, Jules

    2003-06-01

    In the laboratory, Argentine ant, Linepithema humile (Mayr), mortality was positively correlated to the length of an aromatic cedar mulch section that had to be crossed before food could be reached. When ants could access food without crossing the mulch, mortality was not correlated to mulch section length. In the field, Argentine ants showed a tendency to avoid aromatic cedar mulch as a nesting substrate. In plant beds alongside buildings the number of ant nests (pockets containing brood) found was not significantly different between aromatic cedar and cypress mulch. However, when pine straw mulch around oak trees was replaced with aromatic cedar or cypress mulch, a similar number of ant nests was found in the cypress mulch as in the original pine straw, whereas numbers in aromatic cedar mulch were significantly lower. Also, fewer ants were trailing on the trees surrounded by aromatic cedar mulch compared with cypress mulch or the original pine straw. The number of ants attracted to apple jelly baits placed alongside the buildings did not differ between mulch types; neither did the number of ant trails crossing the mulch beds around the buildings. We suggest that aromatic cedar mulch may help control Argentine ants and reduce insecticide input when applied in combination with conventional control methods.

  4. [Preclinical assay of candid #1 vaccine against Argentine Hemorrhagic Fever made in Argentina].

    PubMed

    Ambrosio, Ana M; Riera, Laura M; Saavedra, María del Carmen; Sottosanti, María J

    2005-01-01

    Candid #1 vaccine against Argentine Hemorrhagic Fever produced in USA versus lots of the same vaccine made in Argentina were compared in guinea pigs regarding safety, immunogenicity and protective efficacy against a challenge with pathogenic Junin virus. Lots No Exp 3, 7A and 8A of Argentine origin as well as lot TSI 5-1-92 from USA were inoculated in guinea pigs of 250-400 g in two consecutive assays. Ten animals inoculated with saline performed as normal controls in each experiment. Parameters studied were: a) temperature; b) body weight; c) neutralizing antibodies to Junin virus; d) response to viral challenge. Animals gained weight and remained normothermic up to the challenge. Guinea pigs that received Candid #1 from any manufacturer elicited neutralizing antibodies to Junin virus (titles from 40 to 81920) and survived to challenge whilst 8/10 animals died in each control group. Data presented demonstrated that Candid #1 vaccines from USA or Argentine manufacturers were equally safe, immunogenic and protective in guinea pigs.

  5. Hydrocarbon-released nestmate aggression in the Argentine ant, Linepithema humile, following encounters with insect prey.

    PubMed

    Liang, D; Blomquist, G J; Silverman, J

    2001-07-01

    Argentine ants, Linepithema humile, were attacked by their nestmates following contact with a particular prey item, the brown-banded cockroach, Supella longipalpa. Contact with prey, as brief as 2 min, provoked nestmate aggression. Argentine ants contaminated with hydrocarbons extracted from S. longipalpa also released nestmate aggression behavior similar to that released by the whole prey item, confirming the involvement of hydrocarbons. In contrast to S. longipalpa, little or no nestmate aggression was induced by other ant prey from diverse taxa. A comparison of prey hydrocarbon profiles revealed that all hydrocarbons of S. longipalpa were very long chain components with 33 or more carbons, while other prey had either less, or none, of the very long chain hydrocarbons of 33 carbons or greater. We identified the hydrocarbons of S. longipalpa and some new groups of long chain hydrocarbons of L. humile. The majority of S. longipalpa hydrocarbons were 35 and 37 carbons in length with one to three methyl branches, and closely resembled two previously unidentified groups of compounds from L. humile of similar chain length. The hydrocarbons of S. longipalpa and L. humile were compared and their role in the Argentine ant nestmate recognition is discussed.

  6. Tick loads in cattle raised on sweet and sour rangelands in the low-input farming areas of South Africa.

    PubMed

    Marufu, Munyaradzi C; Chimonyo, Michael; Mapiye, Cletos; Dzama, Kennedy

    2011-02-01

    The objective of this study was to compare tick loads and prevalence in Nguni and non-descript cattle in the sweet (palatable throughout the year) and sour (palatable only in the rainy season) communal rangelands of the Eastern Cape Province, South Africa. Engorged adult female ixodid ticks were collected and identified seasonally from 144 cattle raised on sweet and sour rangelands from August 2007 to April 2008. Three tick species were identified in the sweet and sour rangelands namely Rhipicephalus appendiculatus, Rhipicephalus (Boophilus) decoloratus, and Rhipicephalus evertsi evertsi with prevalences of 71.1%, 29.2%, and 40.2%, respectively. Hyalomma species (19.0%) occurred only in the sour rangeland. Higher tick counts were recorded in the hot-wet season than in the cool-dry season (P < 0.05). Cattle in the sweet rangeland had significantly lower tick loads than those in the sour rangeland in all the seasons except the hot-dry season. The Nguni breed had lower (P < 0.05) tick loads of R. appendiculatus in the hot-wet and post-rainy season and Hyalomma species in all seasons than the non-descript cattle. The use of a tick-resistant Nguni breed in the integrated control of ticks on cattle in the communal areas of South Africa is recommended.

  7. Employing UAVs to Acquire Detailed Vegetation and Bare Ground Data for Assessing Rangeland Health

    NASA Astrophysics Data System (ADS)

    Rango, A.; Laliberte, A.; Herrick, J. E.; Winters, C.

    2007-12-01

    Because of its value as a historical record (extending back to the mid 1930s), aerial photography is an important tool used in many rangeland studies. However, these historical photos are not very useful for detailed analysis of rangeland health because of inadequate spatial resolution and scheduling limitations. These issues are now being resolved by using Unmanned Aerial Vehicles (UAVs) over rangeland study areas. Spatial resolution improvements have been rapid in the last 10 years from the QuickBird satellite through improved aerial photography to the new UAV coverage and have utilized improved sensors and the more simplistic approach of low altitude flights. Our rangeland health experiments have shown that the low altitude UAV digital photography is preferred by rangeland scientists because it allows, for the first time, their identification of vegetation and land surface patterns and patches, gap sizes, bare soil percentages, and vegetation type. This hyperspatial imagery (imagery with a resolution finer than the object of interest) is obtained at about 5cm resolution by flying at an altitude of 150m above the surface of the Jornada Experimental Range in southern New Mexico. Additionally, the UAV provides improved temporal flexibility, such as flights immediately following fires, floods, and other catastrophic disturbances, because the flight capability is located near the study area and the vehicles are under the direct control of the users, eliminating the additional steps associated with budgets and contracts. There are significant challenges to improve the data to make them useful for operational agencies, namely, image distortion with inexpensive, consumer grade digital cameras, difficulty in detecting sufficient ground control points in small scenes (152m by 114m), accuracy of exterior UAV information on X,Y, Z, roll, pitch, and heading, the sheer number of images collected, and developing reliable relationships with ground-based data across a broad

  8. Perceptions of Utah ranchers toward carbon sequestration: policy implications for US rangelands.

    PubMed

    Ma, Zhao; Coppock, D Layne

    2012-11-30

    Enhanced carbon sequestration is one means to mitigate climate change. Rangelands are arid and semi-arid lands, typified by relatively low and variable levels of net primary productivity, where carbon sequestration might be increased via alterations in land management. Rangelands are vast in size and dominate the land area in the western US and worldwide. It has been estimated that privately owned rangelands in the US could sequester an additional 60 million tons of carbon annually, roughly equal to five percent of the US annual CO(2) emissions. Ranchers are the target population that could implement changes in rangeland management to promote carbon sequestration, but little is known about how they might receive such programs. Therefore, for Utah, we conducted a combined mail and telephone survey of 495 randomly selected ranchers to assess their knowledge of and attitude toward carbon sequestration, possible benefits of carbon sequestration as perceived by ranchers, and factors influencing their likelihood of participating in carbon sequestration programs. Overall, despite that 70 percent of respondents had little or no self-reported knowledge about carbon sequestration, 63 percent had negative views about it. Ranchers reporting the most knowledge also tended to have the most negative attitudes. The least important benefit that might accrue to ranchers from carbon sequestration was seen as climate change mitigation, while the most important benefit was improved land stewardship. Only four percent of respondents indicated an unconditional willingness to participate in carbon sequestration programs, but 71 percent could be interested depending on new information received. Before carbon sequestration programs are developed for rangelands, further research is needed to clarify why more knowledge of carbon sequestration can lead to greater skepticism of relevant programs. We respect this finding, as it may be based on well-founded rancher concerns such as technical or

  9. The Haleakala Argentine ant project: a synthesis of past research and prospects for the future.

    USGS Publications Warehouse

    Krushelnycky, Paul; Haines, William; Loope, Lloyd; Van Gelder, Ellen

    2011-01-01

    1. The Haleakala Argentine Ant Project is an ongoing effort to study the ecology of the invasive Argentine ant in the park, and if possible to develop a strategy to control this destructive species. 2. Past research has demonstrated that the Argentine ant causes very significant impacts on native arthropods where it invades, threatening a large portion of the park’s biodiversity in subalpine shrubland and alpine aeolian ecosystems. 3. Patterns of spread over the past 30+ years indicate that the invasion process is influenced to a substantial degree by abiotic factors such as elevation, rainfall and temperature, and that the ant has not reached its potential range. Predictions of total range in the park suggest that it has only invaded a small fraction of available suitable habitat, confirming that this species is one of most serious threats to the park’s natural resources. 4. Numerous experiments have been conducted since 1994 in an attempt to develop a method for eradicating the Argentine ant at Haleakala using pesticidal ant baits. Thirty baits have been screened for attractiveness to ants in the park, and ten of these were tested for effectiveness of control in field plots. While some of these baits have been very effective in reducing numbers of ants, none has been able to eliminate all nests in experimental plots. 5. Research into a secondary management goal of ant population containment was initiated in 1996. By treating only expanding margins of the park’s two ant populations with an ant pesticide, rates of outward spread were substantially reduced in some areas. While this strategy was implemented from 1997 to 2004, it was ultimately discontinued after 2004 because of the difficulty and insufficient effectiveness of the technique. 6. In order to achieve the types of results necessary for eradication, the project would probably need to explore the possibility of developing a specialized bait, rather than relying on a commercially produced bait. An

  10. Recovering Radioactive Materials with ORSP Team

    ScienceCinema

    LANL

    2016-07-12

    The National Nuclear Security Administration sponsors a program, executed by Los Alamos National Laboratory, to recover radioisotopes used by industry and academia and no longer needed. Called the "Offsite Source Recovery Program (OSRP), it has recovered more than 16,000 orphan sources as of 2008.

  11. Mapping soils, crops, and rangelands by machine analysis of multitemporal ERTS-1 data. [Kansas and Texas

    NASA Technical Reports Server (NTRS)

    Baumgardner, M. F.; Henderson, J. A., Jr.

    1974-01-01

    ERTS-1 data, obtained during the period 25 August 1972 to 5 September 1973 over a range of test sites in the Central United States, have been used for identifying and mapping differences in soil patterns, species and conditions of cultivated crops, and conditions of rangelands. Multispectral scanner data from multiple ERTS passes over certain test sites have provided the opportunity to study temporal changes in the scene. Multispectral classifications delineating soils boundaries in different test sites compared well with existing soil association maps prepared by conventional means. Spectral analysis of ERTS data was used to identify, maps, and make areal measurements of wheat in western Kansas. Multispectral analysis of ERTS-1 data provided patterns in rangelands which can be related to soils differences, range management practices, and the extent of infestation of grasslands by mesquite (prosopis fuliflora) and juniper (juniperus spp.).

  12. The value of forage measurement information in rangeland management. [implementation of satellite data in range management

    NASA Technical Reports Server (NTRS)

    Lietzke, K. R.

    1975-01-01

    An economic model and simulation are developed to estimate the potential social benefit arising from the use of alternative measurement systems in rangeland management. In order to estimate these benefits, it was necessary to model three separate systems: the range environment, the rangeland manager, and the information system which links the two. The rancher's decision-making behavior is modeled according to sound economic principles. Results indicate substantial potential benefits, particularly when used in assisting management of government-operated ranges; possible annual benefits in this area range from $20 to $46 million, depending upon the system capabilities assumed. Possible annual benefit in privately-managed stocker operations range from $2.8 to $49.5 million, depending upon where actual rancher capabilities lie and what system capabilities are assumed.

  13. A LANDSAT study of ephemeral and perennial rangeland vegetation and soils

    NASA Technical Reports Server (NTRS)

    Bentley, R. G., Jr. (Principal Investigator); Salmon-Drexler, B. C.; Bonner, W. J.; Vincent, R. K.

    1976-01-01

    The author has identified the following significant results. Several methods of computer processing were applied to LANDSAT data for mapping vegetation characteristics of perennial rangeland in Montana and ephemeral rangeland in Arizona. The choice of optimal processing technique was dependent on prescribed mapping and site condition. Single channel level slicing and ratioing of channels were used for simple enhancement. Predictive models for mapping percent vegetation cover based on data from field spectra and LANDSAT data were generated by multiple linear regression of six unique LANDSAT spectral ratios. Ratio gating logic and maximum likelihood classification were applied successfully to recognize plant communities in Montana. Maximum likelihood classification did little to improve recognition of terrain features when compared to a single channel density slice in sparsely vegetated Arizona. LANDSAT was found to be more sensitive to differences between plant communities based on percentages of vigorous vegetation than to actual physical or spectral differences among plant species.

  14. Secondary compounds in floral rewards of toxic rangeland plants: impacts on pollinators.

    PubMed

    Irwin, Rebecca E; Cook, Daniel; Richardson, Leif L; Manson, Jessamyn S; Gardner, Dale R

    2014-07-30

    The study of plant secondary chemistry has been essential in understanding plant consumption by herbivores. There is growing evidence that secondary compounds also occur in floral rewards, including nectar and pollen. Many pollinators are generalist nectar and pollen foragers and thus are exposed to an array of secondary compounds in their diet. This review documents secondary compounds in the nectar or pollen of poisonous rangeland plants of the western United States and the effects of these compounds on the behavior, performance, and survival of pollinators. Furthermore, the biochemical, physiological, and behavioral mechanisms by which pollinators cope with secondary compound consumption are discussed, drawing parallels between pollinators and herbivores. Finally, three avenues of future research on floral reward chemistry are proposed. Given that the majority of flowering plants require animals for pollination, understanding how floral reward chemistry affects pollinators has implications for plant reproduction in agricultural and rangeland habitats.

  15. Assessment of rangeland ecosystem conditions, Salt Creek watershed and Dugout Ranch, southeastern Utah

    USGS Publications Warehouse

    Bowker, M.A.; Miller, M.E.; Belote, R.T.

    2012-01-01

    Increasingly, dry rangelands are being valued for multiple services beyond their traditional value as a forage production system. Additional ecosystem services include the potential to store carbon in the soil and plant biomass. In addition, dust emissions from rangelands might be considered an ecosystem detriment, the opposite of an ecosystem service. Dust emitted may have far-reaching impacts, for example, reduction of local air quality, as well as altering regional water supplies through effects on snowpack. Using an extensive rangeland monitoring dataset in the greater Canyonlands region (Utah, USA), we developed a method to estimate indices of the provisioning of three ecosystem services (forage production, dust retention, C storage) and one ecosystem property (nativeness), taking into account both ecosystem type and alternative states within that ecosystem type. We also integrated these four indices into a multifunctionality index. Comparing the currently ungrazed Canyonlands National Park watersheds to the adjacent Dugout Ranch pastures, we found clearly higher multifunctionality was attained in the Park, and that this was primarily driven by greater C-storage and better dust retention. It is unlikely to maximize all benefits and minimize all detriments at the same time. Some goods and services may have synergistic interactions; for example, managing for carbon storage will increase plant and biocrust cover likely lowering dust emission. Likewise, some may have antagonistic interactions. For instance, if carbon is consumed as biomass for livestock production, then carbon storage may be reduced. Ultimately our goal should be to quantify the monetary consequences of specific land use practices for multiple ecosystem services and determine the best land use and adaptive management practices for attaining multiple ecosystem services, minimizing economic detriments, and maximizing economic benefits from multi-commodity rangelands. Our technique is the first step

  16. Pastoralists' responses to variation of rangeland resources in time and space.

    PubMed

    McAllister, Ryan R J; Gordon, Iain J; Janssen, Marco A; Abel, Nick

    2006-04-01

    We explore the response of pastoralists to rangeland resource variation in time and space, focusing on regions where high variation makes it unlikely that an economically viable herd can be maintained on a single management unit. In such regions, the need to move stock to find forage in at least some years has led to the evolution of nomadism and transhumance, and reciprocal grazing agreements among the holders of common-property rangeland. The role of such informal institutions in buffering resource variation is well documented in some Asian and African rangelands, but in societies with formally established private-property regimes, where we focus, such institutions have received little attention. We examine agistment networks, which play an important role in buffering resource variation in modern-day Australia. Agistment is a commercial arrangement between pastoralists who have less forage than they believe they require and pastoralists who believe they have more. Agistment facilitates the movement of livestock via a network based largely on trust. We are concerned exclusively with the link between the characteristics of biophysical variation and human aspects of agistment networks, and we developed a model to test the hypothesis that such a link could exist. Our model builds on game theory literature, which explains cooperation between strangers based on the ability of players to learn whom they can trust. Our game is played on a highly stylized landscape that allows us to control and isolate the degree of spatial variation and spatial covariation. We found that agistment networks are more effective where spatial variation in resource availability is high, and generally more effective when spatial covariation is low. Policy design that seeks to work with existing social networks in rangelands has potential, but this potential varies depending on localized characteristics of the biophysical variability.

  17. Nationwide forestry applications program: Procedure 1 applicability to rangeland classification. [Weld County, Colorado

    NASA Technical Reports Server (NTRS)

    Reeves, C. A. (Principal Investigator)

    1978-01-01

    The author has identified the following significant results. An assumption that short prairie grass and salt grass could be differentiated on aircraft photographs was inaccurate for the Weld County site. However, rangeland could be differentiated using procedure 1 from LACIE. Estimates derived from either random or systematic sampling were satisfactory. Level 1 features were separated and mapped, and proportions were estimated with accompanying confidence statements.

  18. Low-cost grass restoration using erosion barriers in a degraded African rangeland

    USGS Publications Warehouse

    Kimiti, David W; Riginos, Corinna; Belnap, Jayne

    2016-01-01

    Rangeland degradation, typified by extensive bare ground and soil erosion, is a serious problem around the world. In sub-Saharan Africa, rangeland degradation threatens the food security of millions of people who depend on livestock and the region's large mammalian wildlife diversity. We tested the ability of five simple, low-cost erosion barriers to promote grass and forb establishment in a bare ground-dominated rangeland in Kenya. These treatments were: (1) trenches with small berms; (2) bundles of branches; and bundles of branches with (3) elephant dung balls, (4) burlap sacking, or (5) nylon mesh sacking inside them. We also tested whether barrier performance depended on (1) supplemental seeding with the grass Cenchrus ciliaris and (2) whether a barrier was located next to existing vegetation patches versus in the open. Within months, the trench and nylon mesh barriers had accumulated 20–50% more sediment than other treatments and had greater grass and forb seedling establishment. Seeding with Cenchrusresulted in higher herbaceous cover but was not necessary for other grasses to establish. After 3 years, the trench and nylon mesh barriers had created patches of new vegetation averaging 18–63% larger than patches created by the other treatments. Barriers that were initially adjacent to existing vegetation had created new vegetation patches averaging 65% larger than those created by solitary barriers. Results suggest that all barrier types increase grass cover but that trenches—especially if placed next to existing vegetation patches—are a particularly cost-effective way to reduce bare ground and erosion in degraded rangelands.

  19. Evaluating Current and Future Rangeland Health in the Great Basin Ecoregion Using NASA Earth Observing Systems

    NASA Astrophysics Data System (ADS)

    Essoudry, E.; Wilson, K.; Ely, J.; Patadia, N.; Zajic, B.; Torres-Perez, J. L.; Schmidt, C.

    2014-12-01

    The Great Basin ecoregion in the western United States represents one of the last large expanses of wild lands in the nation and is currently facing significant challenges due to human impacts, drought, invasive species encroachment such as cheatgrass, and climate change. Rangelands in the Great Basin are of important ecological and economic significance for the United States; however, 40% of public rangelands fail to meet required health standards set by the Bureau of Land Management (BLM). This project provided a set of assessment tools for researchers and land managers that integrate remotely-sensed and in situ datasets to quantify and mitigate threats to public lands in the Great Basin ecoregion. The study area, which accounts for 20% of the total Great Basin ecoregion, was analyzed using 30 m resolution data from Landsat 8. Present conditions were evaluated from vegetation indices, landscape features, hydrological processes, and atmospheric conditions derived from the remotely-sensed data and validated with available in situ ground survey data, provided by the BLM. Rangeland health metrics were developed and landscape change drivers were identified. Subsequently, projected climate conditions derived from the Coupled Model Intercomparison Project (CMIP5) were used to forecast the impact of changing climatic conditions within the study area according to the RCP4.5 and RCP8.5 projections. These forecasted conditions were used in the Maximum Entropy Model (MaxEnt) to predict areas at risk for rangeland degradation on 30 year intervals for 2040, 2070, and 2100. Finally, vegetation health risk maps were provided to the project partners to aid in future land management decisions in the Great Basin ecoregion. These tools provide a low cost solution to assess landscape conditions, provide partners with a metric to identify potential problematic areas, and mitigate serious threats to the ecosystems.

  20. Linking ecosystem services with state-and-transition models to evaluate rangeland management decisions

    NASA Astrophysics Data System (ADS)

    Lohani, S.; Heilman, P.; deSteiguer, J. E.; Guertin, D. P.; Wissler, C.; McClaran, M. P.

    2014-12-01

    Quantifying ecosystem services is a crucial topic for land management decision making. However, market prices are usually not able to capture all the ecosystem services and disservices. Ecosystem services from rangelands, that cover 70% of the world's land area, are even less well-understood since knowledge of rangelands is limited. This study generated a management framework for rangelands that uses remote sensing to generate state and transition models (STMs) for a large area and a linear programming (LP) model that uses ecosystem services to evaluate natural and/or management induced transitions as described in the STM. The LP optimization model determines the best management plan for a plot of semi-arid land in the Empire Ranch in southeastern Arizona. The model allocated land among management activities (do nothing, grazing, fire, and brush removal) to optimize net benefits and determined the impact of monetizing environmental services and disservices on net benefits, acreage allocation and production output. The ecosystem services under study were forage production (AUM/ac/yr), sediment (lbs/ac/yr), water runoff (inches/yr), soil loss (lbs/ac/yr) and recreation (thousands of number of visitors/ac/yr). The optimization model was run for three different scenarios - private rancher, public rancher including environmental services and excluding disservices, and public rancher including both services and disservices. The net benefit was the highest for the public rancher excluding the disservices. A result from the study is a constrained optimization model that incorporates ecosystem services to analyze investments on conservation and management activities. Rangeland managers can use this model to understand and explain, not prescribe, the tradeoffs of management investments.

  1. Phenomapping of rangelands in South Africa using time series of RapidEye data

    NASA Astrophysics Data System (ADS)

    Parplies, André; Dubovyk, Olena; Tewes, Andreas; Mund, Jan-Peter; Schellberg, Jürgen

    2016-12-01

    Phenomapping is an approach which allows the derivation of spatial patterns of vegetation phenology and rangeland productivity based on time series of vegetation indices. In our study, we propose a new spatial mapping approach which combines phenometrics derived from high resolution (HR) satellite time series with spatial logistic regression modeling to discriminate land management systems in rangelands. From the RapidEye time series for selected rangelands in South Africa, we calculated bi-weekly noise reduced Normalized Difference Vegetation Index (NDVI) images. For the growing season of 2011⿿2012, we further derived principal phenology metrics such as start, end and length of growing season and related phenological variables such as amplitude, left derivative and small integral of the NDVI curve. We then mapped these phenometrics across two different tenure systems, communal and commercial, at the very detailed spatial resolution of 5 m. The result of a binary logistic regression (BLR) has shown that the amplitude and the left derivative of the NDVI curve were statistically significant. These indicators are useful to discriminate commercial from communal rangeland systems. We conclude that phenomapping combined with spatial modeling is a powerful tool that allows efficient aggregation of phenology and productivity metrics for spatially explicit analysis of the relationships of crop phenology with site conditions and management. This approach has particular potential for disaggregated and patchy environments such as in farming systems in semi-arid South Africa, where phenology varies considerably among and within years. Further, we see a strong perspective for phenomapping to support spatially explicit modelling of vegetation.

  2. Rangeland monitoring reveals long-term plant responses to precipitation and grazing at the landscape scale

    USGS Publications Warehouse

    Munson, Seth M.; Duniway, Michael C.; Johanson, Jamin K.

    2015-01-01

    Managers of rangeland ecosystems require methods to track the condition of natural resources over large areas and long periods of time as they confront climate change and land use intensification. We demonstrate how rangeland monitoring results can be synthesized using ecological site concepts to understand how climate, site factors, and management actions affect long-term vegetation dynamics at the landscape-scale. Forty-six years of rangeland monitoring conducted by the Bureau of Land Management (BLM) on the Colorado Plateau reveals variable responses of plant species cover to cool-season precipitation, land type (ecological site groups), and grazing intensity. Dominant C3 perennial grasses (Achnatherum hymenoides, Hesperostipa comata), which are essential to support wildlife and livestock on the Colorado Plateau, had responses to cool-season precipitation that were at least twice as large as the dominant C4 perennial grass (Pleuraphis jamesii) and woody vegetation. However, these C3 perennial grass responses to precipitation were reduced by nearly one-third on grassland ecological sites with fine- rather than coarse-textured soils, and there were no detectable C3 perennial grass responses to precipitation on ecological sites dominated by a dense-growing shrub, Coleogyne ramosissima. Heavy grazing intensity further reduced the responses of C3 perennial grasses to cool-season precipitation on ecological sites with coarse-textured soils and surprisingly reduced the responses of shrubs as well. By using ecological site groups to assess rangeland condition, we were able to improve our understanding of the long-term relationships between vegetation change and climate, land use, and site characteristics, which has important implications for developing landscape-scale monitoring strategies.

  3. Remote camera-trap methods and analyses reveal impacts of rangeland management on Namibian carnivore communities

    USGS Publications Warehouse

    Kauffman, M.J.; Sanjayan, M.; Lowenstein, J.; Nelson, A.; Jeo, R.M.; Crooks, K.R.

    2007-01-01

    Assessing the abundance and distribution of mammalian carnivores is vital for understanding their ecology and providing for their long-term conservation. Because of the difficulty of trapping and handling carnivores many studies have relied on abundance indices that may not accurately reflect real abundance and distribution patterns. We developed statistical analyses that detect spatial correlation in visitation data from combined scent station and camera-trap surveys, and we illustrate how to use such data to make inferences about changes in carnivore assemblages. As a case study we compared the carnivore communities of adjacent communal and freehold rangelands in central Namibia. We used an index of overdispersion to test for repeat visits to individual camera-trap scent stations and a bootstrap simulation to test for correlations in visits to camera neighbourhoods. After distilling our presence-absence data to the most defensible spatial scale, we assessed overall carnivore visitation using logistic regression. Our analyses confirmed the expected pattern of a depauparate fauna on the communal rangelands compared to the freehold rangelands. Additionally, the species that were not detected on communal sites were the larger-bodied carnivores. By modelling these rare visits as a Poisson process we illustrate a method of inferring whether or not such patterns are because of local extinction of species or are simply a result of low sample effort. Our Namibian case study indicates that these field methods and analyses can detect meaningful differences in the carnivore communities brought about by anthropogenic influences. ?? 2007 FFI.

  4. Ecosystem performance monitoring of rangelands by integrating modeling and remote sensing

    USGS Publications Warehouse

    Wylie, Bruce K.; Boyte, Stephen P.; Major, Donald J.

    2012-01-01

    Monitoring rangeland ecosystem dynamics, production, and performance is valuable for researchers and land managers. However, ecosystem monitoring studies can be difficult to interpret and apply appropriately if management decisions and disturbances are inseparable from the ecosystem's climate signal. This study separates seasonal weather influences from influences caused by disturbances and management decisions, making interannual time-series analysis more consistent and interpretable. We compared the actual ecosystem performance (AEP) of five rangeland vegetation types in the Owyhee Uplands for 9 yr to their expected ecosystem performance (EEP). Integrated growing season Normalized Difference Vegetation Index data for each of the nine growing seasons served as a proxy for annual AEP. Regression-tree models used long-term site potential, seasonal weather, and land cover data sets to generate annual EEP, an estimate of ecosystem performance incorporating annual weather variations. The difference between AEP and EEP provided a performance measure for each pixel in the study area. Ecosystem performance anomalies occurred when the ecosystem performed significantly better or worse than the model predicted. About 14% of the Owyhee Uplands showed a trend of significant underperformance or overperformance (P<0.10). Land managers can use results from weather-based rangeland ecosystem performance models to help support adaptive management strategies.

  5. Monitoring rangeland plant community composition using spectral mixture analysis of hyperspectral remote sensing data

    NASA Astrophysics Data System (ADS)

    Rochdi, Nadia; Eddy, Peter; Staenz, Karl; Zhang, Jinkai; Lutz, Christian

    2008-10-01

    This paper investigates the abundance mapping of rangeland plant communities using hyperspectral remote sensing data. Spectral Mixture Analysis (SMA) was used to estimate the cover fraction of five rangeland components: green grass, yellow grass, litter, shrubs and soil. Two types of endmembers were assessed using canopy reflectance modeling and tested over real data. The first type is the leaf endmember based on the laboratory reflectance measurements of different samples of leaves. The second is the canopy endmember based on reflectance simulation using the canopy radiative transfer model SAIL. These two endmember types were first assessed in SMA using a number of homogenous canopy simulations with different Leaf Area Index (LAI). Subsequently, the leaf and the canopy endmembers were evaluated using ground spectra, and cover fractions were compared to actual data. Finally, both endmember types were applied in SMA to CHRIS/PROBA data to estimate the rangeland component cover fractions. Performances of leaf and canopy endmembers were evaluated based on the field knowledge of the area of interest. Results showed overall that the cover fraction estimates using the canopy endmembers tend to better agree with actual data.

  6. The Impact of Livestock Grazing on US Rangeland Productive Capacity from 1981 to 2009

    NASA Astrophysics Data System (ADS)

    Washington-Allen, R. A.; Kulawardhana, R. W.; Reeves, M. C.; Mitchell, J. E.

    2010-12-01

    Humans have appropriated an estimated 20% of global net primary productivity (NPP) and 38% of this population is dependant on the $900 billion yr-1 in ecosystem services from drylands that cover 41% of the terrestrial surface. Commercial and subsistence livestock (cattle, sheep, and goats) grazing is embedded in this appropriation and has been implicated in dryland degradation. However, the extent of dryland degradation is unknown with estimates ranging from 10 - 80%. As a solution to this problem, we derived rangeland above-ground biomass or the forage available for grazing from a 1981 - 2009 time-series of 1-km Moderate Resolution Imaging Spectroradiometer (MODIS) NPP and 8-km Advanced Very High Resolution Radiometer Global Inventory Modeling and Mapping Studies (AVHRR-GIMMS) annual summed normalized difference vegetation index (NDVI) data. We derived the forage required by livestock (cattle, sheep, and goats) at the county and state spatial scales from annual agricultural census records that were collected by the United States Department of Agriculture’s National Agricultural Statistics Service (USDA-NASS) from 1981 - 2009. We found that in 2002 US rangelands covered some 257 million ha and that grazing livestock reached 216 million tons of biomass appropriated though only an estimated 149 million tons were available in the US. Consequently, the percentage US rangeland impacted by livestock appropriation of NPP (distributed at the state spatial scale) was 19%. This hotspot was primarily located in southwestern Arizona.

  7. Climate change and land management in the rangelands of central Oregon.

    PubMed

    Creutzburg, Megan K; Halofsky, Jessica E; Halofsky, Joshua S; Christopher, Treg A

    2015-01-01

    Climate change, along with exotic species, disturbances, and land use change, will likely have major impacts on sagebrush steppe ecosystems in the western U.S. over the next century. To effectively manage sagebrush steppe landscapes for long-term goals, managers need information about the interacting impacts of climate change, disturbances and land management on vegetation condition. Using a climate-informed state-and-transition model, we evaluated the potential impacts of climate change on rangeland condition in central Oregon and the effectiveness of multiple management strategies. Under three scenarios of climate change, we projected widespread shifts in potential vegetation types over the twenty-first century, with declining sagebrush steppe and expanding salt desert shrub likely by the end of the century. Many extreme fire years occurred under all climate change scenarios, triggering rapid vegetation shifts. Increasing wildfire under climate change resulted in expansion of exotic grasses but also decreased juniper encroachment relative to projections without climate change. Restoration treatments in warm-dry sagebrush steppe were ineffective in containing exotic grass, but juniper treatments in cool-moist sagebrush steppe substantially reduced the rate of juniper encroachment, particularly when prioritized early in the century. Overall, climate-related shifts dominated future vegetation patterns, making management for improved rangeland condition more difficult. Our approach allows researchers and managers to examine long-term trends and uncertainty in rangeland vegetation condition and test the effectiveness of alternative management actions under projected climate change.

  8. Climate Change and Land Management in the Rangelands of Central Oregon

    NASA Astrophysics Data System (ADS)

    Creutzburg, Megan K.; Halofsky, Jessica E.; Halofsky, Joshua S.; Christopher, Treg A.

    2015-01-01

    Climate change, along with exotic species, disturbances, and land use change, will likely have major impacts on sagebrush steppe ecosystems in the western U.S. over the next century. To effectively manage sagebrush steppe landscapes for long-term goals, managers need information about the interacting impacts of climate change, disturbances and land management on vegetation condition. Using a climate-informed state-and-transition model, we evaluated the potential impacts of climate change on rangeland condition in central Oregon and the effectiveness of multiple management strategies. Under three scenarios of climate change, we projected widespread shifts in potential vegetation types over the twenty-first century, with declining sagebrush steppe and expanding salt desert shrub likely by the end of the century. Many extreme fire years occurred under all climate change scenarios, triggering rapid vegetation shifts. Increasing wildfire under climate change resulted in expansion of exotic grasses but also decreased juniper encroachment relative to projections without climate change. Restoration treatments in warm-dry sagebrush steppe were ineffective in containing exotic grass, but juniper treatments in cool-moist sagebrush steppe substantially reduced the rate of juniper encroachment, particularly when prioritized early in the century. Overall, climate-related shifts dominated future vegetation patterns, making management for improved rangeland condition more difficult. Our approach allows researchers and managers to examine long-term trends and uncertainty in rangeland vegetation condition and test the effectiveness of alternative management actions under projected climate change.

  9. Topographic quantitative EEG amplitude in recovered alcoholics.

    PubMed

    Pollock, V E; Schneider, L S; Zemansky, M F; Gleason, R P; Pawluczyk, S

    1992-05-01

    Topographic measures of electroencephalographic (EEG) amplitude were used to compare recovered alcoholics (n = 14) with sex- and age-matched control subjects. Delta, alpha, and beta activity did not distinguish the groups, but regional differences in theta distribution did. Recovered alcoholics showed more uniform distributions of theta amplitudes in bilateral anterior and posterior regions compared with controls. Because a minimum of 5 years had elapsed since the recovered alcoholic subjects fulfilled DSM-III-R criteria for alcohol abuse or dependence, it is unlikely these EEG theta differences reflect the effects of withdrawal.

  10. Application of high resolution images from unmanned aerial vehicles for hydrology and rangeland science

    NASA Astrophysics Data System (ADS)

    Rango, A.; Vivoni, E. R.; Anderson, C. A.; Perini, N. A.; Saripalli, S.; Laliberte, A.

    2012-12-01

    A common problem in many natural resource disciplines is the lack of high-enough spatial resolution images that can be used for monitoring and modeling purposes. Advances have been made in the utilization of Unmanned Aerial Vehicles (UAVs) in hydrology and rangeland science. By utilizing low flight altitudes and velocities, UAVs are able to produce high resolution (5 cm) images as well as stereo coverage (with 75% forward overlap and 40% sidelap) to extract digital elevation models (DEM). Another advantage of flying at low altitude is that the potential problems of atmospheric haze obscuration are eliminated. Both small fixed-wing and rotary-wing aircraft have been used in our experiments over two rangeland areas in the Jornada Experimental Range in southern New Mexico and the Santa Rita Experimental Range in southern Arizona. The fixed-wing UAV has a digital camera in the wing and six-band multispectral camera in the nose, while the rotary-wing UAV carries a digital camera as payload. Because we have been acquiring imagery for several years, there are now > 31,000 photos at one of the study sites, and 177 mosaics over rangeland areas have been constructed. Using the DEM obtained from the imagery we have determined the actual catchment areas of three watersheds and compared these to previous estimates. At one site, the UAV-derived watershed area is 4.67 ha which is 22% smaller compared to a manual survey using a GPS unit obtained several years ago. This difference can be significant in constructing a watershed model of the site. From a vegetation species classification, we also determined that two of the shrub types in this small watershed(mesquite and creosote with 6.47 % and 5.82% cover, respectively) grow in similar locations(flat upland areas with deep soils), whereas the most predominant shrub(mariola with 11.9% cover) inhabits hillslopes near stream channels(with steep shallow soils). The positioning of these individual shrubs throughout the catchment using

  11. Characterizing rangeland using multispectral remotely sensed data and multi-scale ecological units

    NASA Astrophysics Data System (ADS)

    Maynard, Catherine Cae Lee

    In this study ecological range unit (ERU) delineations combined with multispectral satellite data were examined to address the need for consistent, spatially accurate, and temporally current methods to inventory rangeland and estimate relative biomass productivity in the context of ecologically sensitive site parameters. ERUs, Landsat 7 ETM+ combined band values, and vegetation index data from 13 scenes acquired from June 2000 to August 2002 were used as predictive variables in linear regression estimates of total biomass using field data collected from 263 locations within 24 ecological range sites on 5 Montana ranches. GIS spatial data analysis techniques were applied to certified soils data themes and published landscape level ecological units to produce the ERU categories used to stratify the field data collection and image analysis, and as a method to test the use of an independent data set for addressing the known influence of soil and site variability on the spectral response of vegetation. ERU categories, in combination with the near and mid-infrared bands (Band 4, 0.75--0.90 mum; Band 7 2.09--2.35 mum), were significant independent variables, and in linear regression predictions collectively explained 66% of the variability in total biomass (p -value < 0.001), as compared to 52% explained by the combined bands alone, suggesting that ERU categories might be accounting for a component of soil variability. This report also introduces an efficient, remote sensing directed method for preliminary identification of locations within ERUs where indicators of soil and site stability or biotic integrity might be outside the established means. A comparison between sites with spectrally anomalous brightness, greenness, and wetness Tasseled Cap indices and selected measurements of spectrally sensitive rangeland ecological health indicators were used to develop a classification method for locating and screening rangeland categories. Pixels where site productivity and

  12. Automated monitoring of recovered water quality

    NASA Technical Reports Server (NTRS)

    Misselhorn, J. E.; Hartung, W. H.; Witz, S. W.

    1974-01-01

    Laboratory prototype water quality monitoring system provides automatic system for online monitoring of chemical, physical, and bacteriological properties of recovered water and for signaling malfunction in water recovery system. Monitor incorporates whenever possible commercially available sensors suitably modified.

  13. METHOD FOR RECOVERING URANIUM FROM OILS

    DOEpatents

    Gooch, L.H.

    1959-07-14

    A method is presented for recovering uranium from hydrocarbon oils, wherein the uranium is principally present as UF/sub 4/. According to the invention, substantially complete removal of the uranium from the hydrocarbon oil may be effected by intimately mixing one part of acetone to about 2 to 12 parts of the hydrocarbon oil containing uranium and separating the resulting cake of uranium from the resulting mixture. The uranium in the cake may be readily recovered by burning to the oxide.

  14. Satellite monitoring the rangeland degradation under the impacts of climatic and socio-economic changes over central Asia

    NASA Astrophysics Data System (ADS)

    Wang, K.; Zhang, L.; Dai, L.; Yan, D.

    2012-12-01

    Central Asia, encompassing the republics of Kazakhstan, Kyrgyz, Uzbekistan, Turkmenistan, Tajikistan and China's western Sinkiang, is a typical arid and semi-arid area. The climate in Central Asia is extreme arid, where summer is hot, cloudless and dry, and winter is moist and relatively warm in the south and cold and dry in the north. Rangeland, accounting for 46% of the entire area, is the main vegetation type in this area. Recent findings showed that climate change had caused unprecedented rangeland degradation in Central Asia over the past 30 years. Socio-economical change and environmental change due to the collapse of Soviet Union also accelerated rangeland degradation. Rangeland degradation adversely further deteriorated the environment. With the development of high resolution remote sensing images, an increasing attention has paid to study rangeland degradation in this area. However, previous investigations based on either Advanced Very High Resolution Radiometer (AVHRR) or Moderate Resolution Imaging Spectroradiometer (MODIS) data, has not integrate multi-resolution satellite data for investigating vegetation change and its response to climatic and socio-economic change . In this paper, we employed 30 years' remote sensing data, including both AVHRR ( 1982-2006) and MODIS (2000-2011) satellite data, and in-situ meteorological and social data (e.g. population, economic, and land use change data), to investigate rangeland degradation in the central Asia. We 1) analyzed the spatial-temporal variations of vegetation changes during the past 30 years, and 2) evaluated the roles of climatic and socio-economic factors as potential causes of observed vegetation changes. The results showed extensive area had statistically significant degradation trends (p<0.05). Precipitation was the main driver of rangeland degradation, while there were relatively weaker relationships between temperature and NDVI, indicating that water deficit largely limited vegetation activity

  15. Equity during an economic crisis: financing of the Argentine health system.

    PubMed

    Cavagnero, Eleonora; Bilger, Marcel

    2010-07-01

    This article analyses the redistributive effect caused by health financing and the distribution of healthcare utilization in Argentina before and during the severe 2001/2002 economic crisis. Both dramatically changed during this period: the redistributive effect became much more positive and utilization shifted from pro-poor to pro-rich. This clearly demonstrates that when utilization is contingent on financing, changes can occur rapidly; and that an integrated approach is required when monitoring equity. From a policy perspective, the Argentine health system appears vulnerable to economic downturns mainly due to high reliance on out-of-pocket payments and the strong link between health insurance and employment.

  16. Tolerance and antiviral effect of ribavirin in patients with Argentine hemorrhagic fever.

    PubMed

    Enria, D A; Briggiler, A M; Levis, S; Vallejos, D; Maiztegui, J I; Canonico, P G

    1987-07-01

    Tolerance and antiviral effect of ribavirin was studied in 6 patients with Argentine hemorrhagic fever (AHF) of more than 8 days of evolution. Administration of ribavirin resulted in a neutralization of viremia and a drop of endogenous interferon titers. The average time of death was delayed. A reversible anemia was the only adverse effect observed. From these results, we conclude that ribavirin has an antiviral effect in advanced cases of AHF, and that anemia, the only secondary reaction observed, can be easily managed. The possible beneficial effect of ribavirin during the initial days of AHF is discussed.

  17. In vitro antibacterial activity of Argentine folk medicinal plants against Salmonella typhi.

    PubMed

    Pérez, C; Anesini, C

    1994-08-01

    Boiling water extracts of 132 samples from 54 plant families, commonly used in Argentine folk medicine, were screened for antibacterial activity against Salmonella typhi. The agar-well diffusion method was used. A reference concentration-response curve for ampicillin was used to estimate the apparent activity of the samples. Twenty four species showed antibacterial activity. Cassia occidentalis roots, Heimia salicifolia aerial parts, Punica granatum fruit pericarp and Rosa borboniana flowers produced some of the more active extracts. Taking into account the multiple resistance of Salmonella typhi, these findings could be useful in the search for new clinically useful antimicrobials.

  18. A new species of Havelockia Pearson, 1903 from the Argentine Sea (Holothuroidea: Dendrochirotida: Sclerodactylidae).

    PubMed

    Martinez, Mariano I; Thandar, Ahmed S; Penchaszadeh, Pablo E

    2013-02-04

    Havelockia pegi sp. nov., is here described from shallow waters of the Argentine Sea. This new species is distinctive in the purple colouration of its tentacles, scarcity of body wall ossicles and the presence of rosette-shaped ossicles in both the introvert and the tentacles. It is not closely related to any of its congenors. This is the first record of a true sclerodactylid from Argentina. Thandarum hernandezi Martinez & Brogger, 2012, described in the family Sclerodactylidae, is now classified in the family Sclerothyonidae.

  19. Relationship Between Forage Allowance and Grazing Efficiency in the Great Plains: Implications for Managing Rangelands for Both Livestock Production and Desired Ecosystem Goods and Services

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Emergence of desired ecosystem goods and services from rangelands as a societal benefit and a potential income source for land managers has implications regarding the management of plant communities traditionally used primarily for livestock production. Contemporary decision-making on rangelands in ...

  20. Evaluation of Utah trefoil (Lotus utahensis Ottley) collections for rangeland restoration/revegetation in the southern Great Basin and Colorado Plateau

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wildfires, weed invasion, and various land uses have created a need for revegetation/restoration of rangeland ecosystems in the Intermountain Region of the western U.S.A. These rangelands may require revegetation/restoration to improve degraded conditions, speed recovery after wildfires, minimize s...

  1. Inventory of forest and rangeland and detection of forest stress

    NASA Technical Reports Server (NTRS)

    Heller, R. C. (Principal Investigator); Aldrich, R. C.; Weber, F. P.; Driscoll, R. S.

    1972-01-01

    The author has identified the following significant results. Seventy-two ground sensors were interfaced with three DCP'S at the Black Hills test site. Unfortunately, the transmitters had to be returned for modification and forestry sensed data is not available. The DCP's did operate properly from the Berkeley laboratory and data were recovered from the Goldstone and Alaska stations via Goddard. Replicated training sets and test sets have been selected from all three test site areas in preparation for the receipt of ERTS imagery and digital tapes. From 600 and 800 points have been selected at each site location and UTM coordinates determined. Templates are being made of these sets. As of September 1, ERTS-generated data had not been received and no statements can be made regarding quality or suitability for forest and range experiments. Aerial photography (scale 1:32,000) of the Manitou (226 C) and Black Hills (226 A) sites was taken with CIR in June. Various scales (1:2,000; 1:10,000; 1:20,000; and 1:40,000) of 70 mm photographs were obtained at Manitou with normal color, CIR, and panchromatic in August.

  2. Applications for carbon fibre recovered from composites

    NASA Astrophysics Data System (ADS)

    Pickering; Liu, Z.; Turner, TA; Wong, KH

    2016-07-01

    Commercial operations to recover carbon fibre from waste composites are now developing and as more recovered fibre becomes available new applications for recovered fibre are required. Opportunities to use recovered carbon fibre as a structural reinforcement are considered involving the use of wet lay processes to produce nonwoven mats. Mats with random in-plane fibre orientation can readily be produced using existing commercial processes. However, the fibre volume fraction, and hence the mechanical properties that can be achieved, result in composites with limited mechanical properties. Fibre volume fractions of 40% can be achieved with high moulding pressures of over 100 bar, however, moulding at these pressures results in substantial fibre breakage which reduces the mean fibre length and the properties of the composite manufactured. Nonwoven mats made from aligned, short carbon fibres can achieve higher fibre volume fractions with lower fibre breakage even at high moulding pressure. A process for aligning short fibres is described and a composite of over 60% fibre volume fraction has been manufactured at a pressures up to 100 bar with low fibre breakage. Further developments of the alignment process have been undertaken and a composite of 46% fibre volume fraction has been produced moulded at a pressure of 7 bar in an autoclave, exhibiting good mechanical properties that compete with higher grade materials. This demonstrates the potential for high value applications for recovered carbon fibre by fibre alignment.

  3. Effects of grazing on photosynthetic features and soil respiration of rangelands in the Tianshan Mountains of Northwest China

    PubMed Central

    Liu, Hua; Zang, Runguo; Chen, Han Y. H.

    2016-01-01

    Rangelands play a critical role in the global carbon cycle. However, the eco-physiological mechanisms associated with the effects of grazing on leaf photosynthesis and soil respiration remain poorly understood. To examine the impacts of grazing on leaf photosynthesis and soil respiration, we measured the photosynthetic parameters of the dominant species (Trifolium repens) and the soil respiration in grazed and ungrazed rangelands in the Tianshan Mountains of China. We found that grazing reduced the daily maximum net photosynthetic rate and soil respiration rates by 35% and 15%, respectively. The photosynthetic quantum yield, dark respiratory rate, and water use efficiency of T. repens leaves were reduced in grazed plots by 33.3%, 69.2%, and 21.5%, respectively. Our results demonstrated that grazing reduced carbon assimilation while increasing soil respiration within the rangelands in the Tianshan Mountains. PMID:27452980

  4. Effects of grazing on photosynthetic features and soil respiration of rangelands in the Tianshan Mountains of Northwest China

    NASA Astrophysics Data System (ADS)

    Liu, Hua; Zang, Runguo; Chen, Han Y. H.

    2016-07-01

    Rangelands play a critical role in the global carbon cycle. However, the eco-physiological mechanisms associated with the effects of grazing on leaf photosynthesis and soil respiration remain poorly understood. To examine the impacts of grazing on leaf photosynthesis and soil respiration, we measured the photosynthetic parameters of the dominant species (Trifolium repens) and the soil respiration in grazed and ungrazed rangelands in the Tianshan Mountains of China. We found that grazing reduced the daily maximum net photosynthetic rate and soil respiration rates by 35% and 15%, respectively. The photosynthetic quantum yield, dark respiratory rate, and water use efficiency of T. repens leaves were reduced in grazed plots by 33.3%, 69.2%, and 21.5%, respectively. Our results demonstrated that grazing reduced carbon assimilation while increasing soil respiration within the rangelands in the Tianshan Mountains.

  5. Ergonomic analysis jobs in recovered factories.

    PubMed

    Cuenca, Gabriela; Zotta, Gastón

    2012-01-01

    With the advent of the deep economic crisis in Argentina on 2001, the recovery of companies through to the creation of the Cooperatives Working Self-Management or Factories Recovered by its workers was constituted as one of the ways in which the salaried disobeyed the increasing unemployment. When the companies turn into recovered factories they tend to leave of side practices that have been seen like imposed by the previous organization and not understanding them as a primary condition for the execution of his tasks. Safety and ergonomics are two disciplines that are no longer considered relevant to the daily work. Therefore this investigation aims to revalue, undergo semantic to give back to a place in every organization analyzed. This research developed a self-diagnostic tool for working conditions, and the environment, present in the recovered factories.

  6. Geographical potential of Argentine ants (Linepithema humile Mayr) in the face of global climate change.

    PubMed Central

    Roura-Pascual, Núria; Suarez, Andrew V.; Gómez, Crisanto; Pons, Pere; Touyama, Yoshifumi; Wild, Alexander L.; Peterson, A. Townsend

    2004-01-01

    Determining the spread and potential geographical distribution of invasive species is integral to making invasion biology a predictive science. We assembled a dataset of over 1000 occurrences of the Argentine ant (Linepithema humile), one of the world's worst invasive alien species. Native to central South America, Argentine ants are now found in many Mediterranean and subtropical climates around the world. We used this dataset to assess the species' potential geographical and ecological distribution, and to examine changes in its distributional potential associated with global climate change, using techniques for ecological niche modelling. Models developed were highly predictive of the species' overall range, including both the native distributional area and invaded areas worldwide. Despite its already widespread occurrence, L. humile has potential for further spread, with tropical coastal Africa and southeast Asia apparently vulnerable to invasion. Projecting ecological niche models onto four general circulation model scenarios of future (2050s) climates provided scenarios of the species' potential for distributional expansion with warming climates: generally, the species was predicted to retract its range in tropical regions, but to expand at higher latitude areas. PMID:15615677

  7. Potential application of Northern Argentine propolis to control some phytopathogenic bacteria.

    PubMed

    Ordóñez, R M; Zampini, I C; Moreno, M I Nieva; Isla, M I

    2011-10-20

    The antimicrobial activity of samples of Northern Argentine propolis (Tucumán, Santiago del Estero and Chaco) against phytopathogenic bacteria was assessed and the most active samples were identified. Minimal inhibitory concentration (MIC) values were determined by agar macrodilution and broth microdilution assays. Strong antibacterial activity was detected against Erwinia carotovora spp carotovora CECT 225, Pseudomonas syringae pvar tomato CECT 126, Pseudomonas corrugata CECT 124 and Xanthomonas campestris pvar vesicatoria CECT 792. The most active propolis extract (Tucumán, T1) was selected to bioguide isolation and identified for antimicrobial compound (2',4'-dihydroxychalcone). The antibacterial chalcone was more active than the propolis ethanolic extract (MIC values of 0.5-1 μg ml(-1) and 9.5-15 μg ml(-1), respectively). Phytotoxicity assays were realized and the propolis extracts did not retard germination of lettuce seeds or the growth of onion roots. Propolis solutions applied as sprays on tomato fruits infected with P. syringae reduced the severity of disease. Application of the Argentine propolis extracts diluted with water may be promising for the management of post harvest diseases of fruits.

  8. [Detection of a founder mutation in an Argentine family with hereditary non polyposis colorectal cancer].

    PubMed

    Gómez, Laura; Adi, José; Ibarra, Jorge; Roqué, María

    2010-01-01

    Hereditary non polyposis colorectal cancer (HNPCC) has been related to mutations in the DNA mismatch repair genes (MLH1, MSH2 y MSH6). Mutation detection analysis requires the complete sequencing of these genes, given the high frequency of family-specific alterations. A point mutation (2269-2270insT) in the last codon of the MLH1 gene has been detected in families from a northern region of Italy (Reggio Emilia).Given that this alteration was registered only in people from this region, it has been considered a founder mutation. In this work, we present an Argentine HNPCC family whose ancestors were natives from the Reggio Emilia, Italy, and who were carriers for this mutation. In order to detect the genetic alteration, a PCR was developed followed by a restriction enzyme incubation assay. The mutation was detected in 3 family members, two of them without clinical symptoms. The PCR/restriction enzyme methodology has been sensitive and specific for the detection of this mutation. It has allowed the performance of a pre-symptomatic genetic diagnosis in the Argentine HNPCC family, avoiding sending samples abroad. It is worth mentioning that pre-symptomatic diagnosis of hereditary cancers allows enhanced surveillance and support for the affected families when it is performed by a multidisciplinary group.

  9. Determination of TBT in water and sediment samples along the Argentine Atlantic coast.

    PubMed

    de Waisbaum, R G; Rodriguez, C; Nudelman, N Sbarbati

    2010-11-01

    Cases of imposex have been reported for some organisms living in areas of the Argentine Atlantic coast. Since this is one of the known effects of the anti-fouling agent tributyltin (TBT), quantitative determinations of organotins in samples of water and sediments collected from sites along the Argentine coast were carried out. Severe cases of imposex were first reported for two gastropod species living in the Mar del Plata area, and determinations of TBT in samples collected from this site gave extremely high values and showed a close correlation between the degree of imposex and TBT concentration. Recent investigations in the area have shown a significant decrease. Surveys were also conducted in sites that exhibit highly irregular coastal profiles to examine the relevance of physical environments. Alarming concentrations of TBT were determined in most of the sites where heavy boat traffic and/or marine activities occur, demonstrating the urgent need for regulations to avoid further input of TBT. Reports from other sites in South America reveal that this should be a subject of regional concern in order to avoid severe damage to the biodiversity of regional marine organisms.

  10. Nutrition and interference competition have interactive effects on the behavior and performance of Argentine ants.

    PubMed

    Kay, Adam D; Zumbusch, Taylor; Heinen, Justa L; Marsh, Tom C; Holway, David A

    2010-01-01

    Food availability often influences competitive outcomes through effects on consumer growth. Although it has received less attention, food availability may also affect competition through nutritional effects on behavior. One hypothesis linking nutrition and competition in ants posits that increased access to carbohydrates favors greater investment in worker traits that underlie behavioral dominance. We tested this hypothesis by varying dietary protein:carbohydrate (P:C) ratios and levels of interspecific interference for Argentine ants (Linepithema humile), a widespread invasive species. As predicted, colonies facing interference increased patrolling more when reared on low P:C diets; this result is the first demonstration of an interactive effect of nutrition and interference on ant colonies. Several results suggest that this dietary effect on patrolling was due primarily to changes in colony size rather than worker behavior. Colonies on lower P:C diets had lower worker mortality and larger final colony sizes. Diet had little effect on per capita patrolling, and worker behavior in performance assays depended more on previous exposure to interference than on diet. Our findings indicate that dietary P:C ratios can influence Argentine ant performance in a competitive environment and suggest a mechanism by which monopolization of carbohydrate-rich resources can help invasive ants displace native ant competitors.

  11. Quantitative analysis of the effects of the exotic Argentine ant on seed-dispersal mutualisms

    PubMed Central

    Rodriguez-Cabal, Mariano A.; Stuble, Katharine L.; Nuñez, Martin A.; Sanders, Nathan J.

    2009-01-01

    Although it is increasingly clear that exotic invasive species affect seed-dispersal mutualisms, a synthetic examination of the effect of exotic invasive species on seed-dispersal mutualisms is lacking. Here, we review the impacts of the invasive Argentine ant (Linepithema humile) on seed dispersal. We found that sites with L. humile had 92 per cent fewer native ant seed dispersers than did sites where L. humile was absent. In addition, L. humile did not replace native seed dispersers, as rates of seed removal and seedling establishment were all lower in the presence of L. humile than in its absence. We conclude that potential shifts in plant diversity and concomitant changes in ecosystem function may be a consequence of Argentine ant invasions, as well as invasions by other ant species. Because very few studies have examined the effects of non-ant invasive species on seed-dispersal mutualisms, the prevalence of disruption of seed-dispersal mutualisms by invasive species is unclear. PMID:19465575

  12. Argentine ants (Linepithema humile) use adaptable transportation networks to track changes in resource quality.

    PubMed

    Latty, Tanya; Holmes, Michael J; Makinson, James C; Beekman, Madeleine

    2017-02-15

    Transportation networks play a crucial role in human and animal societies. For a transportation network to be efficient, it must have adequate capacity to meet traffic demand. Network design becomes increasingly difficult in situations where traffic demand can change unexpectedly. In humans, network design is often constrained by path dependency because it is difficult to move a road once it is built. A similar issue theoretically faces pheromone-trail-laying social insects; once a trail has been laid, positive feedback makes re-routing difficult because new trails cannot compete with continually reinforced pre-existing trails. In the present study, we examined the response of Argentine ant colonies and their trail networks to variable environments where resources differ in quality and change unexpectedly. We found that Argentine ant colonies effectively tracked changes in food quality such that colonies allocated the highest proportion of foragers to the most rewarding feeder. Ant colonies maximised access to high concentration feeders by building additional trails and routes connecting the nest to the feeder. Trail networks appeared to form via a pruning process in which lower traffic trails were gradually removed from the network. At the same time, we observed several instances where new trails appear to have been built to accommodate a surge in demand. The combination of trail building when traffic demand is high and trail pruning when traffic demand is low results in a demand-driven network formation system that allows ants to monopolise multiple dynamic resources.

  13. Portrayals of character smoking and drinking in Argentine-, Mexican- and US-produced films.

    PubMed

    Kollath-Cattano, Christy; Abad-Vivero, Erika N; Mejia, Raul; Perez-Hernandez, Rosaura; Sargent, James D; Thrasher, James F

    2016-09-01

    The aim of this study was to assess film character portrayals of tobacco and alcohol use in US and nationally-produced films that were popular in Argentina and Mexico from 2004-2012. We performed a content analysis of these films (n=82 Argentine, 91 Mexican, and 908 US films, respectively). Chi-squares and t-tests were used to compare characteristics of characters who smoked or drank by country of movie production. Then data from all countries were pooled, and generalized estimating equation (GEE) models were used to determine independent correlates of character smoking or drinking. There were 480 major characters for Argentine-, 364 for Mexican-, and 4962 for US-produced films. Smoking prevalence among movie characters was similar to population smoking prevalence in Mexico (21%) and Argentina (26%), but about half in the US (11%), where movie product placements are restricted. Movie smoking declined over the period in all three countries. Movie alcohol prevalence was 40-50% across all countries and did not change with time. Demographic predictors of character smoking included: being male, 18 and older, having negative character valence. Movie smoking was not associated with lower SES. Predictors of character drinking included: being age 18 and older and positive character valence. Smoking and drinking predicted each other, illicit drug use, and higher scores for other risk behaviors. This suggests that policy development in Mexico and Argentina may be necessary to reduce the amount of character tobacco and alcohol use in films.

  14. Optimisation in a natural system: Argentine ants solve the Towers of Hanoi.

    PubMed

    Reid, Chris R; Sumpter, David J T; Beekman, Madeleine

    2011-01-01

    Natural systems are a source of inspiration for computer algorithms designed to solve optimisation problems. Yet most 'nature-inspired' algorithms take only superficial inspiration from biology, and little is known about how real biological systems solve difficult problems. Moreover, ant algorithms, neural networks and similar methods are usually applied to static problems, whereas most biological systems have evolved to perform under dynamically changing conditions. We used the Towers of Hanoi puzzle to test whether Argentine ants can solve a potentially difficult optimisation problem. We also tested whether the ants can adapt to dynamic changes in the problem. We mapped all possible solutions to the Towers of Hanoi on a single graph and converted this into a maze for the ants to solve. We show that the ants are capable of solving the Towers of Hanoi, and are able to adapt when sections of the maze are blocked off and new sections installed. The presence of exploration pheromone increased the efficiency of the resulting network and increased the ants' ability to adapt to changing conditions. Contrary to previous studies, our study shows that mass-recruiting ant species such as the Argentine ant can forage effectively in a dynamic environment. Our results also suggest that novel optimisation algorithms can benefit from stronger biological mimicry.

  15. Geographical potential of Argentine ants (Linepithema humile Mayr) in the face of global climate change.

    PubMed

    Roura-Pascual, Núria; Suarez, Andrew V; Gómez, Crisanto; Pons, Pere; Touyama, Yoshifumi; Wild, Alexander L; Peterson, A Townsend

    2004-12-22

    Determining the spread and potential geographical distribution of invasive species is integral to making invasion biology a predictive science. We assembled a dataset of over 1000 occurrences of the Argentine ant (Linepithema humile), one of the world's worst invasive alien species. Native to central South America, Argentine ants are now found in many Mediterranean and subtropical climates around the world. We used this dataset to assess the species' potential geographical and ecological distribution, and to examine changes in its distributional potential associated with global climate change, using techniques for ecological niche modelling. Models developed were highly predictive of the species' overall range, including both the native distributional area and invaded areas worldwide. Despite its already widespread occurrence, L. humile has potential for further spread, with tropical coastal Africa and southeast Asia apparently vulnerable to invasion. Projecting ecological niche models onto four general circulation model scenarios of future (2050s) climates provided scenarios of the species' potential for distributional expansion with warming climates: generally, the species was predicted to retract its range in tropical regions, but to expand at higher latitude areas.

  16. Robustness and management adaptability in tropical rangelands: a viability-based assessment under the non-equilibrium paradigm.

    PubMed

    Accatino, F; Sabatier, R; De Michele, C; Ward, D; Wiegand, K; Meyer, K M

    2014-08-01

    Rangelands provide the main forage resource for livestock in many parts of the world, but maintaining long-term productivity and providing sufficient income for the rancher remains a challenge. One key issue is to maintain the rangeland in conditions where the rancher has the greatest possibility to adapt his/her management choices to a highly fluctuating and uncertain environment. In this study, we address management robustness and adaptability, which increase the resilience of a rangeland. After reviewing how the concept of resilience evolved in parallel to modelling views on rangelands, we present a dynamic model of rangelands to which we applied the mathematical framework of viability theory to quantify the management adaptability of the system in a stochastic environment. This quantification is based on an index that combines the robustness of the system to rainfall variability and the ability of the rancher to adjust his/her management through time. We evaluated the adaptability for four possible scenarios combining two rainfall regimes (high or low) with two herding strategies (grazers only or mixed herd). Results show that pure grazing is viable only for high-rainfall regimes, and that the use of mixed-feeder herds increases the adaptability of the management. The management is the most adaptive with mixed herds and in rangelands composed of an intermediate density of trees and grasses. In such situations, grass provides high quantities of biomass and woody plants ensure robustness to droughts. Beyond the implications for management, our results illustrate the relevance of viability theory for addressing the issue of robustness and adaptability in non-equilibrium environments.

  17. Soil organic carbon stocks in rangelands of SW Iberian Peninsula as influenced by land degradation

    NASA Astrophysics Data System (ADS)

    Pulido-Fernández, Manuel; Schnabel, Susanne; Francisco Lavado-Contador, Joaquín

    2014-05-01

    Rangelands in SW Iberian Peninsula occupy approximately 95,000 km2 of land grazed by millions of domestic animals. They are characterised by grasslands with varying tree density, interspersed in some areas with shrubs. The herbaceous layer is dominated by annual species and the tree layer is mainly formed of evergreen oak. Most rangelands are exploited in large farms (>100 ha), held mainly on private ownership and dedicated to extensive livestock breeding. Soil organic carbon (SOC) is an essential component of the fertility and productivity in both, natural and human-induced ecosystems. Previous research evidenced SOC is concentrated mainly in the top 5 cm soil layer, displaying large spatial variability, with higher values beneath tree canopies as compared to the open spaces. Traditional practices such as cereal cultivation, as well as an increasing number of domestic animals in the last decades, have been remarked as some of the main causes of SOC depletion in rangelands. However, a better understanding of how livestock grazing affects soil organic carbon stock is still needed. The main objective of this study is to investigate the possible relationships between land degradation and SOC stock in rangelands of SW Iberian Peninsula. Previous studies have shown that sheet erosion is one of the main soil degradation processes. In this study, we have compared SOC stock values from reference soils belonging to a farm where no livestock exists for more than 100 years, with those from 10 farms grazed by domestic animals in the Spanish region of Extremadura. The reference farm is an example of an undisturbed natural area composed of Mediterranean forest and dense scrub. In each farm at least 2 areas were selected, constituting in the case of the grazed farms fenced areas, where the stocking rates could be determined. These units are representative of different rangeland types: wooded rangelands (dehesas), treeless grasslands and scrublands of Retama sphaerocarpa with

  18. Proportion of recovered waterfowl bands reported

    USGS Publications Warehouse

    Geis, A.D.; Atwood, E.L.

    1961-01-01

    Data from the annual mail survey of waterfowl hunters in the United States were used to estimate the total numbers of banded waterfowl that were shot. These estimates were compared with Banding Office records to estimate the proportion of recovered bands that was reported. On the average, about two banded birds were recovered for each one reported. The proportion reported was higher for some areas and for some species than for others. The proportion reported was higher when more of the reports came through employees of conservation agencies.

  19. Solid recovered fuels in the steel industry.

    PubMed

    Kepplinger, Werner L; Tappeiner, Tamara

    2012-04-01

    By using waste materials as alternative fuels in metallurgical plants it is possible to minimize the traditionally used reducing agents, such as coke, coal, oil or natural gas. Moreover, by using waste materials in the metallurgical industry it is feasible to recover these materials as far as possible. This also represents another step towards environmental protection because carbon dioxide emissions can be reduced, if the H(2) content of the waste material is greater in comparison with that of the substituted fuel and the effects of global warming can therefore be reduced. In the present article various solid recovered fuels and their applications in the metallurgical industry are detailed.

  20. Contour ripping is more beneficial than composted manure for restoring degraded rangelands in Central Texas.

    PubMed

    Wilcox, Bradford P; Fox, William E; Prcin, Lisa J; McAlister, Jason; Wolfe, June; Thomas, Diana M; Knight, Robert W; Hoffman, Dennis W; Smeins, Fred E

    2012-11-30

    Rangelands in the United States that have been the site of military training exercises have suffered extensive ecological damage, largely because of soil compaction, creation of ruts, and damage to or destruction of vegetation--all of which lead to higher runoff and accelerated erosion. In this paper we report on a study carried out within the Fort Hood Military Reservation in Central Texas, where we evaluated the extent to which application of composted dairy manure and contour ripping affect soil infiltrability, amount of runoff, and nutrient concentrations in runoff. We conducted experiments at two locations, using rainfall simulation at one and monitoring discharge from small (0.3-ha) watersheds at the other. At the rainfall simulation site, we used six levels of compost application: 4, 8, 12, 16, 20, and 24 Mg/ha. We found that compost application had little effect on runoff, soil infiltration, sediment production, or nutrient concentrations in the runoff--except at the micro-watershed scale (12 and 24 Mg/ha); in this case, nutrient concentrations in runoff were initially high (for the rainfall simulations done immediately after compost application). In contrast, contour ripping--carried out 22 months after compost application on two of the micro-watersheds--was highly effective: runoff on the treated micro-watershed was reduced by half compared with the untreated micro-watershed. Our results suggest that (1) one-time applications of composted dairy manure do little to enhance infiltration of degraded rangelands over the short term (at the same time, these experiments demonstrated that compost application poses very little risk to water quality); and (2) for degraded rangelands with limited infiltration capacity, contour ripping is an effective strategy for increasing infiltration rates.

  1. Incorporating biodiversity into rangeland health: Plant species richness and diversity in great plains grasslands

    USGS Publications Warehouse

    Symstad, A.J.; Jonas, J.L.

    2011-01-01

    Indicators of rangeland health generally do not include a measure of biodiversity. Increasing attention to maintaining biodiversity in rangelands suggests that this omission should be reconsidered, and plant species richness and diversity are two metrics that may be useful and appropriate. Ideally, their response to a variety of anthropogenic and natural drivers in the ecosystem of interest would be clearly understood, thereby providing a means to diagnose the cause of decline in an ecosystem. Conceptual ecological models based on ecological principles and hypotheses provide a framework for this understanding, but these models must be supported by empirical evidence if they are to be used for decision making. To that end, we synthesize results from published studies regarding the responses of plant species richness and diversity to drivers that are of management concern in Great Plains grasslands, one of North America's most imperiled ecosystems. In the published literature, moderate grazing generally has a positive effect on these metrics in tallgrass prairie and a neutral to negative effect in shortgrass prairie. The largest published effects on richness and diversity were caused by moderate grazing in tallgrass prairies and nitrogen fertilization in shortgrass prairies. Although weather is often cited as the reason for considerable annual fluctuations in richness and diversity, little information about the responses of these metrics to weather is available. Responses of the two metrics often diverged, reflecting differences in their sensitivity to different types of changes in the plant community. Although sufficient information has not yet been published for these metrics to meet all the criteria of a good indicator in Great Plains Grasslands, augmenting current methods of evaluating rangeland health with a measure of plant species richness would reduce these shortcomings and provide information critical to managing for biodiversity. ?? Society for Range

  2. Opportunities for Integrated Ecological Analysis across Inland Australia with Standardised Data from Ausplots Rangelands

    PubMed Central

    Guerin, Greg R.; Sparrow, Ben; Tokmakoff, Andrew; Smyth, Anita; Leitch, Emrys; Baruch, Zdravko; Lowe, Andrew J.

    2017-01-01

    Australian rangelands ecosystems cover 81% of the continent but are understudied and continental-scale research has been limited in part by a lack of precise data that are standardised between jurisdictions. We present a new dataset from AusPlots Rangelands that enables integrative rangelands analysis due to its geographic scope and standardised methodology. The method provides data on vegetation and soils, enabling comparison of a suite of metrics including fractional vegetation cover, basal area, and species richness, diversity, and composition. Cover estimates are robust and repeatable, allowing comparisons among environments and detection of modest change. The 442 field plots presented here span a rainfall gradient of 129–1437 mm Mean annual precipitation with varying seasonality. Vegetation measurements include vouchered vascular plant species, growth form, basal area, height, cover and substrate type from 1010 point intercepts as well as systematically recorded absences, which are useful for predictive modelling and validation of remote sensing applications. Leaf and soil samples are sampled for downstream chemical and genomic analysis. We overview the sampling of vegetation parameters and environments, applying the data to the question of how species abundance distributions (SADs) vary over climatic gradients, a key question for the influence of environmental change on ecosystem processes. We found linear relationships between SAD shape and rainfall within grassland and shrubland communities, indicating more uneven abundance in deserts and suggesting relative abundance may shift as a consequence of climate change, resulting in altered diversity and ecosystem function. The standardised data of AusPlots enables such analyses at large spatial scales, and the testing of predictions through time with longitudinal sampling. In future, the AusPlots field program will be directed towards improving coverage of space, under-represented environments, vegetation types

  3. Revolutionary land use change in the 21st century: Is (rangeland) science relevant?

    USGS Publications Warehouse

    Herrick, J.E.; Brown, J.R.; Bestelmeyer, B.T.; Andrews, S.S.; Baldi, G.; Davies, J.; Duniway, M.; Havstad, K.M.; Karl, J.W.; Karlen, D.L.; Peters, Debra P. C.; Quinton, J.N.; Riginos, C.; Shaver, P.L.; Steinaker, D.; Twomlow, S.

    2012-01-01

    Rapidly increasing demand for food, fiber, and fuel together with new technologies and the mobility of global capital are driving revolutionary changes in land use throughout the world. Efforts to increase land productivity include conversion of millions of hectares of rangelands to crop production, including many marginal lands with low resistance and resilience to degradation. Sustaining the productivity of these lands requires careful land use planning and innovative management systems. Historically, this responsibility has been left to agronomists and others with expertise in crop production. In this article, we argue that the revolutionary land use changes necessary to support national and global food security potentially make rangeland science more relevant now than ever. Maintaining and increasing relevance will require a revolutionary change in range science from a discipline that focuses on a particular land use or land cover to one that addresses the challenge of managing all lands that, at one time, were considered to be marginal for crop production. We propose four strategies to increase the relevance of rangeland science to global land management: 1) expand our awareness and understanding of local to global economic, social, and technological trends in order to anticipate and identify drivers and patterns of conversion; 2) emphasize empirical studies and modeling that anticipate the biophysical (ecosystem services) and societal consequences of large-scale changes in land cover and use; 3) significantly increase communication and collaboration with the disciplines and sectors of society currently responsible for managing the new land uses; and 4) develop and adopt a dynamic and flexible resilience-based land classification system and data-supported conceptual models (e.g., state-and-transition models) that represent all lands, regardless of use and the consequences of land conversion to various uses instead of changes in state or condition that are

  4. Mesquite encroachment impact on southern New Mexico rangelands: remote sensing and geographic information systems approach

    NASA Astrophysics Data System (ADS)

    Mohamed, Ahmed H.; Holechek, Jerry L.; Bailey, Derek W.; Campbell, Carol L.; Demers, Michael N.

    2011-01-01

    Honey mesquite (Prosopis glandulosa Torr.) invasion can negatively impact grazing capacity, spatial livestock distribution, and forage production in Chihuahuan Desert rangelands. High spatial resolution remote sensing data can be used to develop maps of shrub encroachment for arid rangelands. The objective of this study was to map changes in honey mesquite abundance and to evaluate honey mesquite impacts on perennial grass production at the Chihuahuan Desert Rangeland Research Center in south-central New Mexico using high resolution satellite imagery. The project employed QuickBird ortho-ready satellite imagery with spatial resolution of 2.4 m in multispectral bands and panchromatic resolution of 0.6 m for the study area on May 19, 2009. We used a maximum likelihood supervised classification algorithm to distinguish honey mesquite from other land cover categories. We then measured grass production (kg/ha) in May, 2009 on 10 permanent, evenly spaced key areas in each pasture. We identified 12×60 m plots from the classified map and used these to calculate honey mesquite canopy cover on the 40 transects across the study area. Areas classified as dominated by honey mesquite estimated from image analyses encompassed 143, 50, 92, and 136 hectares in pastures 1, 4, 14, and 15, respectively. Regression analyses showed that increasing levels of honey mesquite canopy cover corresponded to lower perennial grass forage production (r2 = 0.73, n = 40). Our findings indicate that classification of high-resolution satellite imagery is a very useful tool for mapping invasive shrubs and determining their influence on forage production in desert landscapes.

  5. A potential to monitor nutrients as an indicator of rangeland quality using space borne remote sensing

    NASA Astrophysics Data System (ADS)

    Ramoelo, A.; Cho, M. A.; Madonsela, S.; Mathieu, R.; van der Korchove, R.; Kaszta, Z.; Wolf, E.

    2014-02-01

    Global change consisting of land use and climate change could have huge impacts on food security and the health of various ecosystems. Leaf nitrogen (N) is one of the key factors limiting agricultural production and ecosystem functioning. Leaf N can be used as an indicator of rangeland quality which could provide information for the farmers, decision makers, land planners and managers. Leaf N plays a crucial role in understanding the feeding patterns and distribution of wildlife and livestock. Assessment of this vegetation parameter using conventional methods at landscape scale level is time consuming and tedious. Remote sensing provides a synoptic view of the landscape, which engenders an opportunity to assess leaf N over wider rangeland areas from protected to communal areas. Estimation of leaf N has been successful during peak productivity or high biomass and limited studies estimated leaf N in dry season. The objective of this study is to monitor leaf N as an indicator of rangeland quality using WorldView 2 satellite images in the north-eastern part of South Africa. Series of field work to collect samples for leaf N were undertaken in the beginning of May (end of wet season) and July (dry season). Several conventional and red edge based vegetation indices were computed. Simple regression was used to develop prediction model for leaf N. Using bootstrapping, indicator of precision and accuracy were analyzed to select a best model for the combined data sets (May and July). The may model for red edge based simple ratio explained over 90% of leaf N variations. The model developed from the combined data sets with normalized difference vegetation index explained 62% of leaf N variation, and this is a model used to estimate and map leaf N for two seasons. The study demonstrated that leaf N could be monitored using high spatial resolution with the red edge band capability.

  6. Infection of Melanoplus sanguinipes grasshoppers following ingestion of rangeland plant species harboring vesicular stomatitis virus.

    PubMed

    Drolet, Barbara S; Stuart, Melissa A; Derner, Justin D

    2009-05-01

    Knowledge of the many mechanisms of vesicular stomatitis virus (VSV) transmission is critical for understanding of the epidemiology of sporadic disease outbreaks in the western United States. Migratory grasshoppers [Melanoplus sanguinipes (Fabricius)] have been implicated as reservoirs and mechanical vectors of VSV. The grasshopper-cattle-grasshopper transmission cycle is based on the assumptions that (i) virus shed from clinically infected animals would contaminate pasture plants and remain infectious on plant surfaces and (ii) grasshoppers would become infected by eating the virus-contaminated plants. Our objectives were to determine the stability of VSV on common plant species of U.S. Northern Plains rangelands and to assess the potential of these plant species as a source of virus for grasshoppers. Fourteen plant species were exposed to VSV and assayed for infectious virus over time (0 to 24 h). The frequency of viable virus recovery at 24 h postexposure was as high as 73%. The two most common plant species in Northern Plains rangelands (western wheatgrass [Pascopyrum smithii] and needle and thread [Hesperostipa comata]) were fed to groups of grasshoppers. At 3 weeks postfeeding, the grasshopper infection rate was 44 to 50%. Exposure of VSV to a commonly used grasshopper pesticide resulted in complete viral inactivation. This is the first report demonstrating the stability of VSV on rangeland plant surfaces, and it suggests that a significant window of opportunity exists for grasshoppers to ingest VSV from contaminated plants. The use of grasshopper pesticides on pastures would decrease the incidence of a virus-amplifying mechanical vector and might also decontaminate pastures, thereby decreasing the inter- and intraherd spread of VSV.

  7. Differential use of the Argentine shelf by wintering adults and juveniles southern giant petrels, Macronectes giganteus, from Patagonia

    NASA Astrophysics Data System (ADS)

    Blanco, Gabriela S.; Quintana, Flavio

    2014-08-01

    To study habitat use and at-sea movements of southern giant petrels (SGP) during non-breeding period, we deployed 15 satellite transmitters (six adults, nine juveniles) at Isla Arce and Isla Gran Robredo colonies in Patagonia, Argentina. Birds were instrumented during 81.4 ± 37 days. Adult birds used 74% of the Argentine shelf concentrating mainly at the shelf break, middle shelf waters, and the surroundings of the colony. After fledging, juveniles spread to the Argentine, Uruguayan and Brazilian shelves within the South Atlantic. Adults alternated at-sea excursions (12 ± 5 days) with periods at the colony of 3 ± 0.3 days. Contrarily, juveniles moved first to the shelf break and then traveled northwards reaching the south of Brazil. There was some spatial overlap between age classes, but only during the first 30 days after juveniles had fledged; thereafter there was not overlap between the areas used by both age classes. The Argentine shelf is widely used by different species offering a suitable environment for foraging; this may be why adults SGP from Patagonian colonies spend all year-round within the Argentine shelf. The identification of used areas of non-breeding SGP fills a gap in the species knowledge contributing not only to the preservation the species, but also to the management of marine areas globally recognized as important for many other Procellariiformes.

  8. Sea Level and Ocean Bottom Pressure Variations From Altimetry, Mercator Model and GRACE Mission in the Argentine Basin

    NASA Astrophysics Data System (ADS)

    Garcia-Garcia, D.; Boy, J.; Chao, B. F.

    2008-12-01

    Sea Level Variations (SLV) in the Argentine basin, as already observed from space altimetry missions, show one of the most prominent variances in the oceans. Here we study two major signals in the Argentine basin, the annual and submonthly SLV signals, based on altimetry, various hydrographic data, and the time-variable gravity data from the GRACE mission. We demonstrate that the annual variation is mainly driven by density variations of the water column, that is the steric-SLV. In contrast, the submonthly SLV in the form of the so- called Argentine gyre, a barotropic counterclockwise gyre with a period around 25 days, is mainly mass- induced, that is, mostly produced by mass variations in the region [Fu et al. 2000]. The Argentine gyre signal is well reproduced by the MERCATOR ocean circulation (and bottom pressure) model, unlike the annual signal. We show that now the aliased form (into monthly sampling) is also captured in the GRACE time- variable gravity data after applying appropriated filters; further study awaits higher temporal-resolution GRACE data.

  9. Combining LANDSAT MSS, aerial photographs and ground measurements to estimate rangeland productivity

    NASA Technical Reports Server (NTRS)

    Gialdini, M. J.

    1981-01-01

    The production of a vegetation map of over 2.2 million acres with detail down to the plant community level, and the production of estimates of rangeland productivity (pounds of usable forage per acre for cattle) for a 500,000 acre subset of area with a design goal for accuracy and precision of + or - 20% at the 80% confidence level, are considered. The data consist of five groups: maps of area, LANDSAT data, digital terrain data, large scale aerial photography, and ground plots. An outline of the data acquisition and data reduction schemes are presented.

  10. The potential of Sentinel-2 spectral configuration to assess rangeland quality

    NASA Astrophysics Data System (ADS)

    Ramoelo, Abel; Cho, Moses; Mathieu, Renaud; Skidmore, Andrew K.

    2014-10-01

    The European Space Agency (ESA) has embarked on the development of the Sentinel constellation. Sentinel-2 is intended to improve vegetation assessment at local to global scale. Rangeland quality assessment is crucial for planning and management of grazing areas. Well managed and improved grazing areas lead to higher livestock production, which is a pillar of the rural economy and livelihoods, especially in many parts of the African continent. Leaf nitrogen (N) is an indicator of rangeland quality, and is crucial for understanding ecosystem function and services. Today, estimation of leaf N is possible using field and imaging spectroscopy. However, a few studies based on commercially available multispectral imageries such as WorldView-2 and RapidEye have shown the potential of a red-edge band for accurately predicting and mapping leaf N at the broad landscape scale. Sentinel-2 has two red edge bands. The objective of this study was to investigate the utility of the spectral configuration of Sentinel-2 for estimating leaf N concentration in rangelands and savannas of Southern Africa. Grass canopy reflectance was measured using the FieldSpec 3, Analytical Spectral Device (ASD) in concert with leaf sample collections for leaf N chemical analysis. ASD reflectances were resampled to the spectral bands of Sentinel-2 using published spectral response functions. Random Forest (RF) technique was used to predict leaf N using all thirteen bands. Using leave-one-out cross validation, the RF model explained 90% of leaf N variation, with the root mean square error (RMSE) of 0.04 (6% of the mean). Interestingly, spectral bands centred at 705 nm (red edge) and two shortwave infrared centred at 2190 and 1610 nm were found to be the most important bands in predicting leaf N. These findings concur with previous studies based on spectroscopy, airborne hyperspectral or multispectral imagery, e.g. RapidEye, on the importance of shortwave infrared and red-edge reflectance in the

  11. 27 CFR 19.393 - Restoration and redenaturation of recovered denatured spirits and recovered articles.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Restoration and redenaturation of recovered denatured spirits and recovered articles. 19.393 Section 19.393 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY...

  12. 27 CFR 19.393 - Restoration and redenaturation of recovered denatured spirits and recovered articles.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Restoration and redenaturation of recovered denatured spirits and recovered articles. 19.393 Section 19.393 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY...

  13. Method and apparatus for recovering waste oil

    SciTech Connect

    Kennedy, A.B.

    1982-09-21

    Oil is recovered from a mixture of oil and water by heating the mixture, adding a de-emulsifier, passing the mixture through a first vibrating screen, adding a surface tension reducer, processing through a hydrocyclone, passing through a second vibrating screen, and separating the oil from water by settling.

  14. Process for recovering filler from polymer

    DOEpatents

    Smith, Maurice L.; Smith, Robert M.

    1978-01-01

    This disclosure relates to a process for recovering filler material from a polymeric matrix by reacting the matrix at an elevated temperature in a gas atmosphere with a controlled oxidizing potential and thereafter separating and cleaning the residue from the reaction mixture.

  15. 27 CFR 17.168 - Recovered spirits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Recovered spirits. 17.168 Section 17.168 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... separate alcohol is subject to the registration requirements of 26 U.S.C. 5179 and subpart C of part 29...

  16. Stress Levels of Recovering Drug Addicts.

    ERIC Educational Resources Information Center

    LaMon, Brent C.; Alonzo, Anthony

    It appears that chronic drug use may develop as a means of coping in which individuals use self-medication to produce a more desirable state of being. Because drugs are often used to cope with stress, this study examined stress among recovering male drug addicts (N=23) from an urban substance abuse program by administering a self-report inventory…

  17. Applications for Energy Recovering Free Electron Lasers

    SciTech Connect

    George Neil

    2007-08-01

    The availability of high-power, high-brilliance sources of tunable photons from energy-recovered Free Electron Lasers is opening up whole new fields of application of accelerators in industry. This talk will review some of the ideas that are already being put into production, and some of the newer ideas that are still under development.

  18. Mimosa tenuiflora as a cause of malformations in ruminants in the northeastern Brazilian semiarid rangelands.

    PubMed

    Pimentel, L A; Correa, F Riet; Gardner, D; Panter, K E; Dantas, A F M; Medeiros, R M T; Mota, R A; Araújo, J A S

    2007-11-01

    Craniofacial anomalies, eye malformations, and permanent flexures of the forelimbs are common malformations seen in ruminants grazing semiarid rangelands of Northeastern Brazil. To investigate the cause of these malformations, we fed 2 suspected plants, Mimosa tenuiflora or Prosopis juliflora, to groups of 4 pregnant goats each. Fresh green M. tenuiflora was collected daily and fed ad libitum to 4 goats in group 1 throughout pregnancy. This treatment group also received a supplemental feed concentrate equivalent to 1% body weight. Four goats in group 2 received a ration with 70% of P. juliflora pods and 30% hay throughout pregnancy. Four control goats were fed supplemental feed concentrate (1% body weight) and hay ad libitum throughout pregnancy. Goats treated with P. juliflora pods and the control goats delivered 9 normal kids. The four goats that were fed M. tenuiflora during pregnancy delivered 4 kids, 3 of which had abnormalities similar to those observed in field cases, including cleft lip, unilateral corneal opacity, ocular bilateral dermoids, buphthalmos with a cloudy brownish appearance of the anterior chamber due to an iridal cyst, and segmental stenosis of the colon. Malformations induced experimentally by M. tenuiflora were similar to those observed in field cases, suggesting that M. tenuiflora is a cause of the field cases observed in the Brazilian semiarid rangelands.

  19. Shrub encroachment affects mammalian carnivore abundance and species richness in semiarid rangelands

    NASA Astrophysics Data System (ADS)

    Blaum, Niels; Rossmanith, Eva; Popp, Alexander; Jeltsch, Florian

    2007-01-01

    Shrub encroachment due to overgrazing has led to dramatic changes of savanna landscapes and is considered to be one of the most threatening forms of rangeland degradation e.g. via habitat fragmentation. Mammalian carnivores are particularly vulnerable to local extinction in fragmented landscapes. However, our understanding of how shrub encroachment affects mammalian carnivores is poor. Here we investigated the relative sensitivities of ten native carnivores to different levels of shrub cover ranging from low (<5%) to high shrub cover (>25%) in 20 southern Kalahari rangeland sites. Relative abundance of carnivores was monitored along 40 sand transects (5 m × 250 m) for each site. Our results show that increasing shrub cover affects carnivore species differently. African wild cats, striped polecats, cape foxes and suricates were negatively affected, whereas we found hump-shaped responses for yellow mongooses, bat-eared foxes and small-spotted genets with maximum abundance at shrub covers between 10 and 18%. In contrast, black-backed jackals, slender mongooses and small spotted cats were not significantly affected by increasing shrub cover. However, a negative impact of high shrub cover above 18% was congruent for all species. We conclude that intermediate shrub cover (10-18%) in savanna landscapes sustain viable populations of small carnivores.

  20. Assessing the Effects of Woody Plant Traits on Understory Herbaceous Cover in a Semiarid Rangeland

    NASA Astrophysics Data System (ADS)

    Belay, Tamrat A.; Moe, Stein R.

    2015-07-01

    The ecological impact of woody plant encroachment in rangeland ecosystems has traditionally been evaluated based on correlation studies between densities of dissimilar woody plants and various ecosystem properties. However, ecosystem properties respond differently to woody plant encroachment because of variations in adaptation of co-occurring woody plants. The objective of this study is to predict the impact of woody plant encroachment on understory herbaceous cover based on analysis of key traits of woody plants. We conducted a vegetation survey in 4 savanna sites in southwestern Ethiopia and compared 9 different key traits of 19 co-occurring woody plants with understory herbaceous cover. Our results show that low understory herbaceous cover is associated with evergreen leaf phenology, shrubby growth form, smaller relative crown-base height and larger relative crown diameter. However, the N2-fixing ability and density of woody plants did not influence the understory herbaceous cover. This shows that traits of individual woody plants can predict the impact of woody plant encroachment on understory herbaceous cover better than density does. The finding improves our ability to accurately predict the impact of woody plant encroachment on various ecosystem properties in highly diverse savanna systems. This plant trait-based approach could be also used as an important management exercise to assess and predict the impact of encroaching woody species in several rangeland ecosystems.

  1. Energy budgets and resistances to energy transport in sparsely vegetated rangeland

    USGS Publications Warehouse

    Nichols, W.D.

    1992-01-01

    Partitioning available energy between plants and bare soil in sparsely vegetated rangelands will allow hydrologists and others to gain a greater understanding of water use by native vegetation, especially phreatophytes. Standard methods of conducting energy budget studies result in measurements of latent and sensible heat fluxes above the plant canopy which therefore include the energy fluxes from both the canopy and the soil. One-dimensional theoretical numerical models have been proposed recently for the partitioning of energy in sparse crops. Bowen ratio and other micrometeorological data collected over phreatophytes growing in areas of shallow ground water in central Nevada were used to evaluate the feasibility of using these models, which are based on surface and within-canopy aerodynamic resistances, to determine heat and water vapor transport in sparsely vegetated rangelands. The models appear to provide reasonably good estimates of sensible heat flux from the soil and latent heat flux from the canopy. Estimates of latent heat flux from the soil were less satisfactory. Sensible heat flux from the canopy was not well predicted by the present resistance formulations. Also, estimates of total above-canopy fluxes were not satisfactory when using a single value for above-canopy bulk aerodynamic resistance. ?? 1992.

  2. The usefullness of ERTS-1 and supporting aircraft data for monitoring plant development in rangeland environments

    NASA Technical Reports Server (NTRS)

    Carneggie, D. M.; Degloria, S. D.

    1972-01-01

    The author has identified the following significant results. Preliminary analysis of ERTS-1 MSS imagery of annual and perennial rangeland in California yields the following observations: (1) Sufficient geomorphological detail can be resolved to differentiate upland and bottomland range sites in the foothill range areas. (2) Dry and green meadowland can be differentiated on MSS band 5. (3) Color composites prepared by NASA-Goddard were useful for locating perennial rangeland with varying amounts of herbaceous ground cover. (4) The ERTS-1 images received and interpreted cover nearly 50% of the state of California and show nearly two-thirds of the annual grassland type. (5) Satellite imagery obtained during the late summer season should be optimum for differentiating grassland from brushland and forested land. (6) The ERTS-1 imagery clearly shows areas which at one time were part of the annual grassland but which are now used for dry land farming (cropping of cereal grains). Similarly, the imagery show areas which have been converted from brushland to grassland.

  3. Building bridges using livestock as ecosystem engineers in semi-arid rangelands: Addressing conservation and livestock production goals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Domestic livestock have the potential to function as ecosystem engineers in semi-arid rangelands, but their utility has been compromised by management practices that emphasize livestock production, homogeneous use of vegetation and removal/control of interacting disturbances of fire and prairie dogs...

  4. Performance of the rangeland hydrology and erosion model for runoff and erosion assessment on a semiarid reclaimed construction site

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability to assess the impact of management actions on soil and water resources is crucial to sustainable land management. The Rangeland Hydrology and Erosion Model (RHEM) was developed as an assessment and decision support tool for resource management agencies and has been used to estimate soil...

  5. Multiscale assessment of green leaf area in a semi-arid rangeland with a small unmanned aerial vehicle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spatial variability in green leaf cover of a western rangeland was studied by comparing field measurements on 50 m crossed transects to aerial and satellite imagery. The normalized difference vegetation index was calculated for multiple 2 cm resolution images collected over the field transects with ...

  6. Geospatial datasets for assessing the effects of rangeland conditions on dissolved-solids yields in the Upper Colorado River Basin

    USGS Publications Warehouse

    Tillman, Fred D; Flynn, Marilyn E.; Anning, David W.

    2015-01-01

    In 2009, the U.S. Geological Survey (USGS) developed a Spatially Referenced Regressions on Watershed Attributes (SPARROW) surface-water quality model for the Upper Colorado River Basin (UCRB) relating dissolved-solids sources and transport in the 1991 water year to upstream catchment characteristics. The SPARROW model focused on geologic and agricultural sources of dissolved solids in the UCRB and was calibrated using water-year 1991 dissolved-solids loads from 218 monitoring sites. A new UCRB SPARROW model is planned that will update the investigation of dissolved-solids sources and transport in the basin to circa 2010 conditions and will improve upon the 2009 model by incorporating more detailed information about agricultural-irrigation and rangeland-management practices, among other improvements. Geospatial datasets relating to circa 2010 rangeland conditions are required for the new UCRB SPARROW modeling effort. This study compiled geospatial datasets for the UCRB that relate to the biotic alterations and rangeland conditions of grazing, fire and other land disturbance, and vegetation type and cover. Datasets representing abiotic alterations of access control (off-highway vehicles) and sediment generation and transport in general, were also compiled. These geospatial datasets may be tested in the upcoming SPARROW model to better understand the potential contribution of rangelands to dissolved-solids loading in UCRB streams.

  7. The changing role of shrubs in rangeland-based livestock production systems: Can shrubs increase our forage supply?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Projected global increases in ruminant numbers and loss of native grasslands will present a number of challenges for livestock agriculture. Escalated demand for livestock products may stimulate interest in using shrubs on western rangelands. A paradigm shift is needed to change the role of shrubs in...

  8. Integrated climate and land use change scenarios for California rangeland ecosystem services: wildlife habitat, soil carbon, and water supply

    USGS Publications Warehouse

    Byrd, Kristin B.; Flint, Lorraine E.; Alvarez, Pelayo; Casey, Frank; Sleeter, Benjamin M.; Soulard, Christopher E.; Flint, Alan L.; Sohl, Terry L.

    2015-01-01

    Results support the need for climate-smart land use planning that takes recharge areas into account, which will provide opportunities for water storage in dry years. Given projections for agriculture, more modeling is needed on feedbacks between agricultural expansion on rangelands and water supply.

  9. Vegetation cover and volume estimates in semi-arid rangelands using LiDAR and hyperspectral data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sagebrush covers 1.1 x 106 km2 of North American rangelands and is an important cover type for many species. Like most vegetation, sagebrush cover and height varies across the landscape. Accurately mapping this variation is important for certain species, such as the greater sage-grouse, where sagebr...

  10. Potential for using visual, auditory, and olfactory cues to manage foraging behaviour and spatial distribution of rangeland livestock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper reviews the literature and reports on the current state of knowledge regarding the potential for managers to use visual (VC), auditory (AC), and olfactory (OC) cues to manage foraging behavior and spatial distribution of rangeland livestock. We present evidence that free-ranging livestock...

  11. Marker-trait association of rangeland and turf traits in hybrids of Festuca idahoensis and Festuca ovina

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fine fescue species Festuca idahoensis Elmer is native to the Intermountain West and has potential for low-input turf and rangeland applications. The poor seed production and weak seedling vigor of this species may be overcome by identification and improvement of interspecific hybrids between F...

  12. Control of Downy brome (Bromus tectorum) and Medusahead (Taeniatherum caput-medusae) With Rangeland Herbicides in Northeastern California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Downy brome and medusahead are the most problematic invasive annual grasses in rangelands of the western United States. In this study, we evaluated the effect of three fall-applied, and one spring-applied, herbicides or combinations on the control of these two invasive grasses in a sagebrush communi...

  13. Can imazapic and seeding be applied simultaneously to rehabilitate medusahead-invaded rangeland? Single vs. multiple entry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It has recently been proposed that reducing the cost of rehabilitating medusahead (Taeniatherum caput-medusae (L.) Nevski)-invaded rangelands may be attained by seeding desired vegetation with a concurrent application of the pre-emergent herbicide (imazapic). However, the efficacy of this “single e...

  14. VegMeasure 2: A software package that facilitates measurement of foliar cove, litter, and bareground on rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the most important indicators of rangeland condition and health is the percentage of the soil that is covered and protected from raindrops and overland flow of water by plants and litter. Sequential measurements of cover at seasonal or yearly intervals can indicate range trend. Unfortunately...

  15. Effects of feral free-roaming horses on semi-arid rangeland ecosystems: an example from the sagebrush steppe

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feral horses (Equus caballus) are viewed as a symbol of freedom and power; however, they are also a largely unmanaged, non-native grazer in North America, South America, and Australia. Information on their influence on vegetation and soil characteristics in semi-arid rangelands has been limited by ...

  16. Sediment Budgets and Source Determinations Using Fallout Cesium-137 in a Semiarid Rangeland Watershed in Arizona, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Analysis of soil redistribution and sediment sources in semiarid and arid watersheds provides information for implementing management practices to improve rangeland conditions and reduce sediment loads to streams. The purpose of this research was to develop sediment budgets and to identify potentia...

  17. Effects of sand sagebrush control in southern mixed-grass prairie rangeland on cattle performance and economic return

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To evaluate the effects of sand sagebrush (Artemisia filifolia Torr.) control in native rangelands on cattle performance, 15 pastures (10 to 21 ha each) were selected in Northwest Oklahoma. Eleven pastures had been sprayed with 2,4-dichlorophenoxyacetic acid in 1984 or 2003 to establish differences...

  18. Apparatus for separating and recovering hydrogen isotopes

    DOEpatents

    Heung, Leung K.

    1994-01-01

    An apparatus for recovering hydrogen and separating its isotopes. The apparatus includes a housing bearing at least a fluid inlet and a fluid outlet. A baffle is disposed within the housing, attached thereto by a bracket. A hollow conduit is coiled about the baffle, in spaced relation to the baffle and the housing. The coiled conduit is at least partially filled with a hydride. The hydride can be heated to a high temperature and cooled to a low temperature quickly by circulating a heat transfer fluid in the housing. The spacing between the baffle and the housing maximizes the heat exchange rate between the fluid in the housing and the hydride in the conduit. The apparatus can be used to recover hydrogen isotopes (protium, deuterium and tritium) from gaseous mixtures, or to separate hydrogen isotopes from each other.

  19. Emergency destruction system for recovered chemical munitions

    SciTech Connect

    Shepodd, T.J.; Stofleth, J.H.; Haroldsen, B.L.

    1998-04-01

    At the request of the US Army Project Manager for Non-Stockpile Chemical Materiel, Sandia National Laboratories is developing a transportable system for destroying recovered, explosively configured, chemical warfare munitions. The system uses shaped charges to access the agent and burster followed by chemical neutralization to destroy them. The entire process takes place inside a sealed pressure vessel. In this paper, they review the design, operation, and testing of a prototype system capable of containing up to one pound of explosive.

  20. Method of recovering oil-based fluid

    SciTech Connect

    Brinkley, H.E.

    1993-07-13

    A method is described of recovering oil-based fluid, said method comprising the steps of: applying an oil-based fluid absorbent cloth of man-made fiber to an oil-based fluid, the cloth having at least a portion thereof that is napped so as to raise ends and loops of the man-made fibers and define voids; and absorbing the oil-based fluid into the napped portion of the cloth.

  1. Recovering intrinsic fluorescence by Monte Carlo modeling.

    PubMed

    Müller, Manfred; Hendriks, Benno H W

    2013-02-01

    We present a novel way to recover intrinsic fluorescence in turbid media based on Monte Carlo generated look-up tables and making use of a diffuse reflectance measurement taken at the same location. The method has been validated on various phantoms with known intrinsic fluorescence and is benchmarked against photon-migration methods. This new method combines more flexibility in the probe design with fast reconstruction and showed similar reconstruction accuracy as found in other reconstruction methods.

  2. Recovering selenium from copper refinery slimes

    NASA Astrophysics Data System (ADS)

    Hyvärinen, Olli; Lindroos, Leo; Yllö, Erkki

    1989-07-01

    The selenium contained within copper refinery slimes may be recovered advantageously by roasting at about 600°C. While roasting in air is inefficient, roasting in a sulfating atmosphere enables practically complete selenium recovery. Based on laboratory tests, a new selenium recovery process was adopted at Outokumpu Copper Refinery. In this process, sulfation is achieved by feeding sulfur dioxide and oxygen into the roasting furnace.

  3. Method for recovering metals from waste

    DOEpatents

    Wicks, George G.; Clark, David E.; Schulz, Rebecca L.

    1998-01-01

    A method for recovering metals from metals-containing wastes, and vitrifying the remainder of the wastes for disposal. Metals-containing wastes such as circuit boards, cathode ray tubes, vacuum tubes, transistors and so forth, are broken up and placed in a suitable container. The container is heated by microwaves to a first temperature in the range of approximately 300.degree.-800.degree. C. to combust organic materials in the waste, then heated further to a second temperature in the range of approximately 1,000.degree.-1,550.degree. C. at which temperature glass formers present in the waste will cause it to melt and vitrify. Low-melting-point metals such as tin and aluminum can be recovered after organics combustion is substantially complete. Metals with higher melting points, such as gold, silver and copper, can be recovered from the solidified product or separated from the waste at their respective melting points. Network former-containing materials can be added at the start of the process to assist vitrification.

  4. Method for recovering metals from waste

    DOEpatents

    Wicks, George G.; Clark, David E.; Schulz, Rebecca L.

    2000-01-01

    A method for recovering metals from metals-containing wastes, and vitrifying the remainder of the wastes for disposal. Metals-containing wastes such as circuit boards, cathode ray tubes, vacuum tubes, transistors and so forth, are broken up and placed in a suitable container. The container is heated by microwaves to a first temperature in the range of approximately 300-800.degree. C. to combust organic materials in the waste, then heated further to a second temperature in the range of approximately 1,000-1,550.degree. C. at which temperature glass formers present in the waste will cause it to melt and vitrify. Low-melting-point metals such as tin and aluminum can be recovered after organics combustion is substantially complete. Metals with higher melting points, such as gold, silver and copper, can be recovered from the solidified product or separated from the waste at their respective melting points. Network former-containing materials can be added at the start of the process to assist vitrification.

  5. Method for recovering materials from waste

    DOEpatents

    Wicks, G.G.; Clark, D.E.; Schulz, R.L.

    1994-01-01

    A method for recovering metals from metals-containing wastes, a vitrifying the remainder of the wastes for disposal. Metals-containing wastes such as circuit boards, cathode ray tubes, vacuum tubes, transistors and so forth, are broken up and placed in a suitable container. The container is heated by microwaves to a first temperature in the range of approximately 300--800{degrees}C to combust organic materials in the waste, then heated further to a second temperature in the range of approximately 1000--1550{degrees}C at which temperature glass formers present in the waste will cause it to melt and vitrify. Low-melting-point metals such as tin and aluminum can be recovered after organics combustion is substantially complete. Metals with higher melting points, such as gold, silver and copper, can be recovered from the solidified product or separated from the waste at their respective melting points. Network former-containing materials can be added at the start of the process to assist vitrification.

  6. Method for recovering metals from waste

    DOEpatents

    Wicks, G.G.; Clark, D.E.; Schulz, R.L.

    1998-12-01

    A method is described for recovering metals from metals-containing wastes, and vitrifying the remainder of the wastes for disposal. Metals-containing wastes such as circuit boards, cathode ray tubes, vacuum tubes, transistors and so forth, are broken up and placed in a suitable container. The container is heated by microwaves to a first temperature in the range of approximately 300--800 C to combust organic materials in the waste, then heated further to a second temperature in the range of approximately 1,000--1,550 C at which temperature glass formers present in the waste will cause it to melt and vitrify. Low-melting-point metals such as tin and aluminum can be recovered after organics combustion is substantially complete. Metals with higher melting points, such as gold, silver and copper, can be recovered from the solidified product or separated from the waste at their respective melting points. Network former-containing materials can be added at the start of the process to assist vitrification. 2 figs.

  7. Valvulopathy consistent with endocarditis in an Argentine boa (Boa constrictor occidentalis).

    PubMed

    Wernick, Morena B; Novo-Matos, José; Ebling, Alessia; Kühn, Karolin; Ruetten, Maja; Hilbe, Monika; Howard, Judith; Chang, Rita; Prohaska, Sarah; Hatt, Jean-Michel

    2015-03-01

    An Argentine boa (Boa constrictor occidentalis) of 5 yr 7 mo of age was presented for respiratory problems and regurgitation. Radiographs revealed evidence of cardiomegaly and pneumonia. Blood smear examination revealed the presence of intracytoplasmic inclusion bodies in peripheral lymphocytes, consistent with inclusion body disease. Cultures of a tracheal wash sample resulted in growth of Ochrobactrum intermedium and Pseudomonas putida. Echocardiographic examination revealed a large vegetative lesion on the right atrioventricular valve with valvular insufficiency, a mildly dilated right atrium, and pulmonary hypertension. Postmortem examination confirmed the presence of pneumonia and bacterial endocarditis with dystrophic mineralization of the right atrioventricular valve, associated with different bacteria than those cultured from the tracheal wash. The present case is the first report of endocarditis in a boa constrictor and contributes to the rare reports of cardiac disease in snakes.

  8. Basis for the implementation of digital signature in Argentine's health environment

    NASA Astrophysics Data System (ADS)

    Escobar, P. P.; Formica, M.

    2007-11-01

    The growth of telemedical applications and electronic transactions in health environments is paced by the constant technology evolution. This implies a big cultural change in traditional medicine and in hospital information systems' users which arrival is delayed, basically, by the lack of solid laws and a well defined role-based infrastructure. The use of digital signature as a mean of identification, authentication, confidentiality and non-repudiation is the most suitable tool for assuring the electronic transactions and patient's data protection. The implementation of a Public Key Infrastructure (PKI) in health environment allows for authentication, encryption and use of digital signature for assuring confidentiality and control of the movement of sensitive information. This work defines the minimum technological, legal and procedural basis for a successful PKI implementation and establishes the roles for the different actors in the chain of confidence in the public health environment of Argentine.

  9. Adjective checklist to assess the big five personality factors in the Argentine population.

    PubMed

    Ledesma, Rubén D; Sánchez, Roberto; Díaz-Lázaro, Carlos M

    2011-01-01

    The aim of this work was to develop an adjective checklist to assess the Big Five personality factors in the Argentine population. The new instrument was administered to pilot (n= 112), validation (n= 372), and replication (n= 309) samples. The final version of the checklist included 67 adjectives encompassing its 5 dimensions. Factor analysis results were consistent with the Five-factor model. Internal consistency of scales was very good and convergent correlations with the Big Five Inventory (BFI; John, Donahue, & Kentle, 1991) were substantial. Face validity, as evaluated by 2 independent raters, was good. Preliminary evidence of validity for the checklist is presented. Finally, the Adjective Checklist for Personality Assessment and BFI are compared, taking into consideration their psychometric properties in our cultural context. Study limitations and future research are discussed.

  10. Screening of plants used in Argentine folk medicine for antimicrobial activity.

    PubMed

    Anesini, C; Perez, C

    1993-06-01

    Screening of 132 extracts from Argentine folk-medicinal plants for antimicrobial activity has been conducted using a penicillin G resistant strain of Staphylococcus aureus, Escherichia coli and Aspergillus niger as test microorganisms. Cephazolin, ampicillin and miconazole were used as standard antibiotics and concentration-response curves were obtained using the agar-well diffusion method. Boiling water extracts of plant materials were tested and 12 species were active against Staphylococcus aureus, whereas 10 were effective against Escherichia coli and 4 against Aspergillus niger. Tabebuia impetiginosa bark, Achyrocline sp. aerials parts, Larrea divaricata leaves, Rosa borboniana flowers, Punica granatum fruit pericarp, Psidium guineense fruit pericarp, Lithrea ternifolia leaves and Allium sativum bulbs produced some of the more active extracts.

  11. Protective efficacy of a live attenuated vaccine against Argentine hemorrhagic fever. AHF Study Group.

    PubMed

    Maiztegui, J I; McKee, K T; Barrera Oro, J G; Harrison, L H; Gibbs, P H; Feuillade, M R; Enria, D A; Briggiler, A M; Levis, S C; Ambrosio, A M; Halsey, N A; Peters, C J

    1998-02-01

    Argentine hemorrhagic fever (AHF), caused by the arenavirus Junin, is a major public health problem among agricultural workers in Argentina. A prospective, randomized, double-blind, placebo-controlled, efficacy trial of Candid 1, a live attenuated Junin virus vaccine, was conducted over two consecutive epidemic seasons among 6500 male agricultural workers in the AHF-endemic region. Twenty-three men developed laboratory-confirmed AHF during the study; 22 received placebo and 1 received vaccine (vaccine efficacy 95%; 95% confidence interval [CI], 82%-99%). Three additional subjects in each group developed laboratory-confirmed Junin virus infection associated with mild illnesses that did not fulfill the clinical case definition for AHF, yielding a protective efficacy for prevention of any illness associated with Junin virus infection of 84% (95% CI, 60%-94%). No serious adverse events were attributed to vaccination. Candid 1, the first vaccine for the prevention of illness caused by an arenavirus, is safe and highly efficacious.

  12. Junin virus replication in peripheral blood mononuclear cells of patients with Argentine haemorrhagic fever.

    PubMed

    Ambrosio, M; Vallejos, A; Saavedra, C; Maiztegui, J I

    1990-02-01

    To study the relationship of Junin virus (JV) to populations of peripheral blood mononuclear cells (PBMC) from patients with Argentine Haemorrhagic Fever (AHF), blood samples were obtained during the acute period of disease and cultured as total, adherent, and non-adherent cell populations. JV was sequentially sought in these cell populations by using an Infectious Centre (IC) assay, whereas free JV in the supernatants was evaluated by plaque formation. IC were obtained in cultures of total PBMC from 8 out of 19 patients. Maximum numbers of IC showed high variation among patients, ranging from 3 to 410 IC per 10(6) viable PBMC. In contrast, IC were sporadically demonstrated in the non-adherent cell population. The release of JV into culture supernatants was detected only in total PBMC cultures, thus in the presence of macrophages. These results demonstrate that circulating monocytes (macrophages) are targets for JV replication contributing to the viral spread in the acute phase of AHF.

  13. Use of remote sensing and GIS to identify Flamingo habitat in the Argentine Altiplano

    USGS Publications Warehouse

    Boyle, Susan C.; Hoffer, Roger M.; Boyle, Terence P.; Bucher, Enrique H.

    1992-01-01

    The Argentine altiplano is a remote area which has never been adequately mapped. It is an arid region with harsh climate, little vegetation, sparse population, and an average elevation of over 3,500 feet. Little is known about the large populations of three species of flamingos which nest and feed in the altiplano lakes. In a study funded by the National Geographic Society satellite data (Landsat MSS and TM data) were used to map the location of major water bodies and to analyze the spectral characteristics of the aquatic ecosystems in the altiplano. A comparison of the two images revealed dramatic changes in the size, depth, and spectral reflectance of the lakes utilized by the flamingos.

  14. Development and validation of an Argentine set of facial expressions of emotion.

    PubMed

    Vaiman, Marcelo; Wagner, Mónica Anna; Caicedo, Estefanía; Pereno, Germán Leandro

    2017-02-01

    Pictures of facial expressions of emotion are used in a wide range of experiments. The last decade has seen an increase in the number of studies presenting local sets of emotion stimuli. However, only a few existing sets contain pictures of Latin Americans, despite the growing attention emotion research is receiving in this region. Here we present the development and validation of the Universidad Nacional de Cordoba, Expresiones de Emociones Faciales (UNCEEF), a Facial Action Coding System (FACS)-verified set of pictures of Argentineans expressing the six basic emotions, plus neutral expressions. FACS scores, recognition rates, Hu scores, and discrimination indices are reported. Evidence of convergent validity was obtained using the Pictures of Facial Affect in an Argentine sample. However, recognition accuracy was greater for UNCEEF. The importance of local sets of emotion pictures is discussed.

  15. First finding of melanic sylvatic Triatoma infestans (Hemiptera: Reduviidae) colonies in the Argentine Chaco.

    PubMed

    Ceballos, L A; Piccinali, R V; Berkunsky, I; Kitron, U; Gürtler, R E

    2009-09-01

    Triatoma infestans (Klug), the most important vector of Chagas disease in southern South America, is a highly domiciliated species with well-known sylvatic foci only in the Bolivian Andean valleys and in the Bolivian Chaco, where melanic insects designated as "dark morphs" were found. After the tentative identification of two melanic bugs collected from parrot nests in a forest reserve in the Argentine Chaco as T. infestans, we conducted an intensive search there using mouse-baited sticky traps in summer 2006 and 2007. Four live T. infestans bugs were collected in trees without parrot nests in 288 trap-nights, whereas no bug was collected from inside trees with active parrot nests in 51 trap-nights. To increase bug captures, hollow tree trunks that recently had had Amazona aestiva (Berlepsch) and Aratinga acuticaudata (Vieillot) parrot nests were treated with insecticide fumigant canisters exhibiting strong knockdown power. Four (22%) of 18 trees were positive for T. infestans with a dark phenotype. A fragment of the mitochondrial gene COI of 8 of the 14 triatomine bugs collected was successfully sequenced and confirmed as T. infestans. Most of the bugs were captured from Aspidosperma quebracho-blanco (Schlechter) hollow tree trunks harboring parrot nests. All of the T. infestans collected from the nearest house located at 10 km from the sylvatic foci displayed normal chromatic characters. The repeated finding of T. infestans in sylvatic habitats, albeit at very low density, shows that this species is capable of maintaining viable sylvatic foci in the absence of human hosts and immigration from domestic populations. These are the first confirmed findings of sylvatic T. infestans colonies in Argentina and of dark morphs in the Argentine Chaco.

  16. Marine fronts are important fishing areas for demersal species at the Argentine Sea (Southwest Atlantic Ocean)

    NASA Astrophysics Data System (ADS)

    Alemany, Daniela; Acha, Eduardo M.; Iribarne, Oscar O.

    2014-03-01

    The high primary and secondary production associated with frontal systems attract a diversity of organisms due to high prey availability; this is why a strong relationship between fronts and pelagic fisheries has been shown worldwide. In the Argentine Sea, demersal resources are the most important, both in economical and in ecological sense; so we hypothesize that fronts are also preferred fishing areas for demersal resources. We evaluated the relationship between spatial distribution of fishing effort and oceanographic fronts, analyzing three of the most important frontal systems located in the Argentine Sea: the shelf-break front, the southern Patagonia front and the mid-shelf front. Individual vessel satellite monitoring system data (VMS; grouped by fleet type: ice-trawlers, freezer-trawlers and jigging fleet) were studied and fishing events were identified. Fishing events per area were used as a proxy of fishing effort and its spatial distribution by fleet type was visualized and analyzed with Geographic Information Systems. Oceanographic fronts were defined using polygons based on satellite chlorophyll amplitude values, and the percentage of fishing events within each polygon was calculated. Results showed a positive association between fronts and fishing activities of the different fleets, which suggests the aggregation of target species in these zones. The coupling of the freezer-trawler and jigging fleets (that operate on lower trophic level species; Macruronus magellanicus and Illex argentinus respectively) with fronts was higher than the ice-trawler fleet, targeting species of higher trophic level (Merluccius hubbsi). Marine fronts represent important fishing areas, even for demersal resources, as the distribution of fishing fleets and fishing effort are positively associated with frontal zones.

  17. First Finding of Melanic Sylvatic Triatoma infestans (Hemiptera: Reduviidae) Colonies in the Argentine Chaco

    PubMed Central

    CEBALLOS, L. A.; PICCINALI, R. V.; BERKUNSKY, I.; KITRON, U.; GÜRTLER, R. E.

    2009-01-01

    Triatoma infestans (Klug), the most important vector of Chagas disease in southern South America, is a highly domiciliated species with well-known sylvatic foci only in the Bolivian Andean valleys and in the Bolivian Chaco, where melanic insects designated as “dark morphs” were found. After the tentative identification of two melanic bugs collected from parrot nests in a forest reserve in the Argentine Chaco as T. infestans, we conducted an intensive search there using mouse-baited sticky traps in summer 2006 and 2007. Four live T. infestans bugs were collected in trees without parrot nests in 288 trap-nights, whereas no bug was collected from inside trees with active parrot nests in 51 trap-nights. To increase bug captures, hollow tree trunks that recently had had Amazona aestiva (Berlepsch) and Aratinga acuticaudata (Vieillot) parrot nests were treated with insecticide fumigant canisters exhibiting strong knockdown power. Four (22%) of 18 trees were positive for T. infestans with a dark phenotype. A fragment of the mitochondrial gene COI of 8 of the 14 triatomine bugs collected was successfully sequenced and confirmed as T. infestans. Most of the bugs were captured from Aspidosperma quebracho-blanco (Schlechter) hollow tree trunks harboring parrot nests. All of the T. infestans collected from the nearest house located at 10 km from the sylvatic foci displayed normal chromatic characters. The repeated finding of T. infestans in sylvatic habitats, albeit at very low density, shows that this species is capable of maintaining viable sylvatic foci in the absence of human hosts and immigration from domestic populations. These are the first confirmed findings of sylvatic T. infestans colonies in Argentina and of dark morphs in the Argentine Chaco. PMID:19769054

  18. Consequences of the Argentine ant, Linepithema humile (Mayr), invasion on pollination of Euphorbia characias (L.) (Euphorbiaceae)

    NASA Astrophysics Data System (ADS)

    Blancafort, Xavier; Gómez, Crisanto

    2005-07-01

    We have studied the influence of the Argentine ant, Linepithema humile, on the pollination of Euphorbia characias, a deciduous insect-pollinated shrub. The observations were made in two adjacent areas (invaded and non-invaded by L. humile) in a Mediterranean cork-oak forest. In the invaded area, L. humile has replaced most of the native ants that climb up this plant's inflorescences. Five native ant species were detected in the non-invaded areas and only one in the invaded area. The number of visitors to infested inflorescences (1.54 ± 1.86 visitors/10 min observation) was lower than in non-infested inflorescences in the invaded area (3.74 ± 4.19 visitors/10'), and in the non-invaded areas (4.16 ± 5.00 visits/10'). For several species of flower-visiting insects, no differences were detected between the time spent in the flowers and the number of flowers visited in the two areas, except for Eristalis tenax, a dipteran which visited more flowers (15.2 ± 11.1 flowers visited/10') and spent more time (9.4 ± 5.8 sec) in the non-invaded area than in the invaded area (7.8 ± 8.2 flowers visited/10' and 5.3 ± 2.1 sec, respectively). The relative representation of insect orders in the two areas was not different. A significant reduction in fruit-set and seed-set was detected in the invaded area. These results suggest that the Argentine ant may greatly affect the reproductive success of components of the Mediterranean flora.

  19. Can the Argentine ant ( Linepithema humile Mayr) replace native ants in myrmecochory?

    NASA Astrophysics Data System (ADS)

    Gómez, Crisanto; Oliveras, Jordi

    2003-04-01

    We analyse the influence of the Argentine ant ( Linepithema humile Mayr) on the seed dispersal process of the myrmecochorous plants Euphorbia characias, E. biumbellata, Genista linifolia, G. triflora, G. monspessulana and Sarothamnus arboreus. The observations were made in two study plots of Mediterranean cork-oak secondary forest (invaded and non-invaded by L. humile). The presence of L. humile implies the displacement of all native ant species that disperse seeds. Seed transports in the non-invaded zone were carried out by eight ant species. In the invaded zone, L. humile workers removed and transported seeds to the nest. In vertebrate exclusion trials, we observed the same level of seed removal in the invaded and non-invaded zones. Two findings could explain this result. Although mean time to seed localization was higher for native ants (431.7 s) than that for L. humile (150.5 s), the mean proportion of seeds transported after being detected was higher (50.1%) in non-invaded than in invaded (16.8%) zones. The proportion of seeds removed and transported into an ant nest after an ant-seed interaction had dramatically reduced from non-invaded (41.9%) to invaded (7.4%) zones. The levels of seed dispersal by ants found prior to invasion are unlikely to be maintained in invaded zones. However, total replacement of seed dispersal function is possible if contact iteration finally offers similar levels or quantities of seeds reaching the nests. The results obtained confirm that the Argentine ant invasion may affect myrmecochory dramatically in the Mediterranean biome.

  20. By their own devices: invasive Argentine ants have shifted diet without clear aid from symbiotic microbes.

    PubMed

    Hu, Yi; Holway, David A; Łukasik, Piotr; Chau, Linh; Kay, Adam D; LeBrun, Edward G; Miller, Katie A; Sanders, Jon G; Suarez, Andrew V; Russell, Jacob A

    2017-03-01

    The functions and compositions of symbiotic bacterial communities often correlate with host ecology. Yet cause-effect relationships and the order of symbiont vs. host change remain unclear in the face of ancient symbioses and conserved host ecology. Several groups of ants exemplify this challenge, as their low-nitrogen diets and specialized symbioses appear conserved and ancient. To address whether nitrogen-provisioning symbionts might be important in the early stages of ant trophic shifts, we studied bacteria from the Argentine ant, Linepithema humile - an invasive species that has transitioned towards greater consumption of sugar-rich, nitrogen-poor foods in parts of its introduced range. Bacteria were present at low densities in most L. humile workers, and among those yielding quality 16S rRNA amplicon sequencing data, we found just three symbionts to be common and dominant. Two, a Lactobacillus and an Acetobacteraceae species, were shared between native and introduced populations. The other, a Rickettsia, was found only in two introduced supercolonies. Across an eight-year period of trophic reduction in one introduced population, we found no change in symbionts, arguing against a relationship between natural dietary change and microbiome composition. Overall, our findings thus argue against major changes in symbiotic bacteria in association with the invasion and trophic shift of L. humile. In addition, genome content from close relatives of the identified symbionts suggests that just one can synthesize most essential amino acids; this bacterium was only modestly abundant in introduced populations, providing little support for a major role of nitrogen-provisioning symbioses in Argentine ant's dietary shift.

  1. Floral visitation by the Argentine ant reduces bee visitation and plant seed set.

    PubMed

    Hanna, Cause; Naughton, Ida; Boser, Christina; Alarcón, Ruben; Hung, Keng-Lou James; Holway, David

    2015-01-01

    Ants often visit flowers, but have only seldom been documented to provide effective pollination services. Floral visitation by ants can also compromise plant reproduction in situations where ants interfere with more effective pollinators. Introduced ants may be especially likely to reduce plant reproductive success through floral visitation, but existing experimental studies have found little support for this hypothesis. Here, we combine experimental and observational approaches to examine the importance of floral visitation by the nonnative Argentine ant (Linepithema humile) on plant species native to Santa Cruz Island, California, USA. First, we determine how L. humile affects floral visitor diversity, bee visitation rates, and levels of pollen limitation for the common, focal plant species island morning glory (Calystegia macrostegia ssp. macrostegia). Second, we assess the broader ecological consequences of floral visitation by L. humile by comparing floral visitation networks between invaded and uninvaded sites. The Argentine ant and native ants both visited island morning glory flowers, but L. humile was much more likely to behave aggressively towards other floral visitors and to be the sole floral occupant. The presence of L. humile in morning glory flowers reduced floral visitor diversity, decreased rates of bee visitation, and increased levels of pollen limitation. Network comparisons between invaded and uninvaded. sites revealed differences in both network structure and species-level attributes. In. invaded sites, floral visitors were observed on fewer plant species, ants had a higher per-plant interaction strength relative to that of other visitors, and interaction strengths between bees and plants were weaker. These results illustrate that introduced ants can negatively affect plant reproduction and potentially disrupt pollination services at an ecosystem scale.

  2. The interconnectedness between landowner knowledge, value, belief, attitude, and willingness to act: policy implications for carbon sequestration on private rangelands.

    PubMed

    Cook, Seth L; Ma, Zhao

    2014-02-15

    Rangelands can be managed to increase soil carbon and help mitigate emissions of carbon dioxide. This study assessed Utah rangeland owner's environmental values, beliefs about climate change, and awareness of and attitudes towards carbon sequestration, as well as their perceptions of potential policy strategies for promoting carbon sequestration on private rangelands. Data were collected from semi-structured interviews and a statewide survey of Utah rangeland owners, and were analyzed using descriptive and bivariate statistics. Over two-thirds of respondents reported some level of awareness of carbon sequestration and a generally positive attitude towards it, contrasting to their lack of interest in participating in a relevant program in the future. Having a positive attitude was statistically significantly associated with having more "biocentric" environmental values, believing the climate had been changing over the past 30 years, and having a stronger belief of human activities influencing the climate. Respondents valued the potential ecological benefits of carbon sequestration more than the potential financial or climate change benefits. Additionally, respondents indicated a preference for educational approaches over financial incentives. They also preferred to work with a private agricultural entity over a non-profit or government entity on improving land management practices to sequester carbon. These results suggest potential challenges for developing technically sound and socially acceptable policies and programs for promoting carbon sequestration on private rangelands. Potential strategies for overcoming these challenges include emphasizing the ecological benefits associated with sequestering carbon to appeal to landowners with ecologically oriented management objectives, enhancing the cooperation between private agricultural organizations and government agencies, and funneling resources for promoting carbon sequestration into existing land management and

  3. Rangeland Condition Monitoring: A New Approach Using Cross-Fence Comparisons of Remotely Sensed Vegetation

    PubMed Central

    Kilpatrick, Adam D.; Lewis, Megan M.; Ostendorf, Bertram

    2015-01-01

    A need exists in arid rangelands for effective monitoring of the impacts of grazing management on vegetation cover. Monitoring methods which utilize remotely-sensed imagery may have comprehensive spatial and temporal sampling, but do not necessarily control for spatial variation of natural variables, such as landsystem, vegetation type, soil type and rainfall. We use the inverse of the red band from Landsat TM satellite imagery to determine levels of vegetation cover in a 22,672km2 area of arid rangeland in central South Australia. We interpret this wealth of data using a cross-fence comparison methodology, allowing us to rank paddocks (fields) in the study region according to effectiveness of grazing management. The cross-fence comparison methodology generates and solves simultaneous equations of the relationship between each paddock and all other paddocks, derived from pairs of cross-fence sample points. We compare this ranking from two image dates separated by six years, during which management changes are known to have taken place. Changes in paddock rank resulting from the cross-fence comparison method show strong correspondence to those predicted by grazing management in this region, with a significant difference between the two common management types; a change from full stocking rate to light 20% stocking regime (Major Stocking Reduction) and maintenance of full 100% stocking regime (Full Stocking Maintained) (P = 0.00000132). While no paddocks had a known increase in stocking rate during the study period, many had a reduction or complete removal in stock numbers, and many also experienced removals of pest species, such as rabbits, and other ecosystem restoration activities. These paddocks generally showed an improvement in rank compared to paddocks where the stocking regime remained relatively unchanged. For the first time, this method allows us to rank non-adjacent paddocks in a rangeland region relative to each other, while controlling for natural spatio

  4. Rangeland Condition Monitoring: A New Approach Using Cross-Fence Comparisons of Remotely Sensed Vegetation.

    PubMed

    Kilpatrick, Adam D; Lewis, Megan M; Ostendorf, Bertram

    2015-01-01

    A need exists in arid rangelands for effective monitoring of the impacts of grazing management on vegetation cover. Monitoring methods which utilize remotely-sensed imagery may have comprehensive spatial and temporal sampling, but do not necessarily control for spatial variation of natural variables, such as landsystem, vegetation type, soil type and rainfall. We use the inverse of the red band from Landsat TM satellite imagery to determine levels of vegetation cover in a 22,672 km(2) area of arid rangeland in central South Australia. We interpret this wealth of data using a cross-fence comparison methodology, allowing us to rank paddocks (fields) in the study region according to effectiveness of grazing management. The cross-fence comparison methodology generates and solves simultaneous equations of the relationship between each paddock and all other paddocks, derived from pairs of cross-fence sample points. We compare this ranking from two image dates separated by six years, during which management changes are known to have taken place. Changes in paddock rank resulting from the cross-fence comparison method show strong correspondence to those predicted by grazing management in this region, with a significant difference between the two common management types; a change from full stocking rate to light 20% stocking regime (Major Stocking Reduction) and maintenance of full 100% stocking regime (Full Stocking Maintained) (P = 0.00000132). While no paddocks had a known increase in stocking rate during the study period, many had a reduction or complete removal in stock numbers, and many also experienced removals of pest species, such as rabbits, and other ecosystem restoration activities. These paddocks generally showed an improvement in rank compared to paddocks where the stocking regime remained relatively unchanged. For the first time, this method allows us to rank non-adjacent paddocks in a rangeland region relative to each other, while controlling for natural

  5. Long-term livestock exclusion facilitates native woody plant encroachment in a sandy semiarid rangeland

    PubMed Central

    Su, Hua; Liu, Wei; Xu, Hong; Wang, Zongshuai; Zhang, Huifang; Hu, Haixiao; Li, Yonggeng

    2015-01-01

    The role of livestock grazing in regulating woody cover and biomass in grass-dominant systems is well recognized. However, the way in which woody plant populations in respond when livestock are removed from grazing in the absence of other disturbances, such as fire, remains unclear. We conducted a 10-year, replicated fencing experiment in a sandy semiarid rangeland in northern China (which has a mean annual rainfall of 365 mm), where fires have been actively suppressed for decades. Fencing dramatically influenced the growth and age structure of the native tree species, Ulmus pumila, which is the sole dominant tree in the area. After a decade, the density of the U. pumila tree population in the fencing plots increased doubly and canopy cover increased triply. The proportion of both saplings (U2) and young trees (U3) increased in fencing plots but decreased in grazing plots after the 10-year treatment period. The effects of fencing on U. pumila trees varied by age class, with potential implications for the future structure of the U. pumila tree community. Decadal fencing led to approximately 80-fold increase in recruitment and a nearly 2.5-fold decrease in the mortality of both U2 and U3. Further, livestock grazing generated a “browsing trap” to the recruitment of both U2 and U3, and had a small impact on the mortality of old trees. A long-term, fencing-driven shift in woody species composition was mediated via its effects on both recruitment and mortality rates. Synthesis and applications. Our results demonstrate that in the long-term absence of both fire and livestock, native woody plant encroachment tends to occur in sandy rangelands, transforming the woody plant demography in the process. The feasibility of full livestock exclusion in sandy rangelands requires further discussion. A balanced amount of livestock grazing may provide critical ecosystem services by regulating woody cover and mediating woody plant encroachment. PMID:26120433

  6. Long-term livestock exclusion facilitates native woody plant encroachment in a sandy semiarid rangeland.

    PubMed

    Su, Hua; Liu, Wei; Xu, Hong; Wang, Zongshuai; Zhang, Huifang; Hu, Haixiao; Li, Yonggeng

    2015-06-01

    The role of livestock grazing in regulating woody cover and biomass in grass-dominant systems is well recognized. However, the way in which woody plant populations in respond when livestock are removed from grazing in the absence of other disturbances, such as fire, remains unclear.We conducted a 10-year, replicated fencing experiment in a sandy semiarid rangeland in northern China (which has a mean annual rainfall of 365 mm), where fires have been actively suppressed for decades.Fencing dramatically influenced the growth and age structure of the native tree species, Ulmus pumila, which is the sole dominant tree in the area. After a decade, the density of the U. pumila tree population in the fencing plots increased doubly and canopy cover increased triply. The proportion of both saplings (U 2 ) and young trees (U 3 ) increased in fencing plots but decreased in grazing plots after the 10-year treatment period. The effects of fencing on U. pumila trees varied by age class, with potential implications for the future structure of the U. pumila tree community. Decadal fencing led to approximately 80-fold increase in recruitment and a nearly 2.5-fold decrease in the mortality of both U 2 and U 3 . Further, livestock grazing generated a "browsing trap" to the recruitment of both U 2 and U 3 , and had a small impact on the mortality of old trees. A long-term, fencing-driven shift in woody species composition was mediated via its effects on both recruitment and mortality rates.Synthesis and applications. Our results demonstrate that in the long-term absence of both fire and livestock, native woody plant encroachment tends to occur in sandy rangelands, transforming the woody plant demography in the process. The feasibility of full livestock exclusion in sandy rangelands requires further discussion. A balanced amount of livestock grazing may provide critical ecosystem services by regulating woody cover and mediating woody plant encroachment.

  7. Bush Encroachment and Soil Biochemistry: Controls and Feedbacks in Kalahari Rangelands

    NASA Astrophysics Data System (ADS)

    Dougill, A. J.; Thomas, A. D.

    2003-12-01

    In the Kalahari of Southern Africa the main ecological change following cattle-based agricultural intensification has been grass removal and bush encroachment, notably of Acacia mellifera. A conceptual 'state-and-transition' model has expressed changes to vegetation communities in Kalahari rangelands. However, many uncertainties remain as to the controls, processes and feedbacks leading to bush encroachment, due to previous inadequate spatial scales of data collection. The aim of integrated research from four sites across the Kalahari was to characterise the controls and feedbacks between ecological changes, soil properties and livestock grazing. Key research questions include: Do changes in soil water and nutrient cycling occur with, and/or cause, bush encroachment?; and, what mechanisms can explain the perceived resilience of Kalahari soils? Research includes process studies of nutrient leaching and mineralization; controlled plot studies examining the impacts of surface nutrient inputs and disturbance; local-scale analyses of spatial patterns of soil biochemistry and bush cover; and ranch-scale assessments of ecology and soil properties. The results demonstrate that bush encroachment has not been caused by, nor is it associated with, increased leaching of soil water and nutrients into the subsoil. Nutrient adsorption in the surface layer explains much of the resilience to soil chemical changes, together with the low mineralization rates that enable synchrony between nutrient availability and plant uptake by surface roots. The main encroaching bush species all have extensive surface rooting systems to enable their competitive dominance following intensive grazing. Bush encroachment is associated with increased spatial heterogeneity of surface nutrients with enhanced concentrations under bush canopies. This enrichment results from both plant canopy inputs, and the more extensive biological soil crust cover found in protected sub-canopy niches. As total nutrient

  8. Sahelian rangeland response to changes in rainfall over two decades in the Gourma region, Mali

    NASA Astrophysics Data System (ADS)

    Hiernaux, Pierre; Mougin, Eric; Diarra, Lassine; Soumaguel, Nogmana; Lavenu, François; Tracol, Yann; Diawara, Mamadou

    2009-08-01

    SummaryTwenty-five rangeland sites were monitored over two decades (1984-2006) first to assess the impact of the 1983-1984 droughts on fodder resources, then to better understand ecosystem functioning and dynamics. Sites are sampled along the south-north bioclimatic gradient in Gourma (Mali), within three main edaphic situations: sandy, loamy-clay and shallow soils. In addition, three levels of grazing pressure where systematically sampled within sandy soils. Located at the northern edge of the area reached by the West African monsoon, the Gourma gradient has recorded extremes in inter-annual variations of rainfall and resulting variations in vegetation growth. Following rainfall variability, inter-annual variability of herbaceous yield increases as climate gets dryer with latitudes at least on the sandy soils sites. Local redistribution of rainfall explains the high patchiness of herbaceous vegetation, especially on shallow soils. Yet spatial heterogeneity of the vegetation does not buffer between year yield variability that increases with spatial heterogeneity. At short term, livestock grazing during the wet season affects plant growth and thus yield in direction and proportions that vary with the timing and intensity of grazing. In the longer term, grazing also impinges upon species composition in many ways. Hence, long histories of heavy grazing promote either long cycle annuals refused by livestock or else short cycle good quality feed species. Primary production is maintained or even increased in the case of refusal such as Sida cordifolia, and is lessened in the case of short cycle species such as Zornia glochidiata. These behaviours explain that the yield anomalies calculated for the rangelands on sandy soils relative to the yield of site less grazed under similar climate tend to be negative in northern Sahel where the scenario of short cycle species dominates, while yield anomalies are close to nil in centre Sahel and slightly positive in South Sahel where

  9. Recovering hydrocarbons from hydrocarbon-containing vapors

    DOEpatents

    Mirza, Zia I.; Knell, Everett W.; Winter, Bruce L.

    1980-09-30

    Values are recovered from a hydrocarbon-containing vapor by contacting the vapor with quench liquid consisting essentially of hydrocarbons to form a condensate and a vapor residue, the condensate and quench fluid forming a combined liquid stream. The combined liquid stream is mixed with a viscosity-lowering liquid to form a mixed liquid having a viscosity lower than the viscosity of the combined liquid stream to permit easy handling of the combined liquid stream. The quench liquid is a cooled portion of the mixed liquid. Viscosity-lowering liquid is separated from a portion of the mixed liquid and cycled to form additional mixed liquid.

  10. Recovering the fine structures in solar images

    NASA Technical Reports Server (NTRS)

    Karovska, Margarita; Habbal, S. R.; Golub, L.; Deluca, E.; Hudson, Hugh S.

    1994-01-01

    Several examples of the capability of the blind iterative deconvolution (BID) technique to recover the real point spread function, when limited a priori information is available about its characteristics. To demonstrate the potential of image post-processing for probing the fine scale and temporal variability of the solar atmosphere, the BID technique is applied to different samples of solar observations from space. The BID technique was originally proposed for correction of the effects of atmospheric turbulence on optical images. The processed images provide a detailed view of the spatial structure of the solar atmosphere at different heights in regions with different large-scale magnetic field structures.

  11. Recovering valuable metals from recycled photovoltaic modules.

    PubMed

    Yi, Youn Kyu; Kim, Hyun Soo; Tran, Tam; Hong, Sung Kil; Kim, Myong Jun

    2014-07-01

    Recovering valuable metals such as Si, Ag, Cu, and Al has become a pressing issue as end-of-life photovoltaic modules need to be recycled in the near future to meet legislative requirements in most countries. Of major interest is the recovery and recycling of high-purity silicon (> 99.9%) for the production of wafers and semiconductors. The value of Si in crystalline-type photovoltaic modules is estimated to be -$95/kW at the 2012 metal price. At the current installed capacity of 30 GW/yr, the metal value in the PV modules represents valuable resources that should be recovered in the future. The recycling of end-of-life photovoltaic modules would supply > 88,000 and 207,000 tpa Si by 2040 and 2050, respectively. This represents more than 50% of the required Si for module fabrication. Experimental testwork on crystalline Si modules could recover a > 99.98%-grade Si product by HNO3/NaOH leaching to remove Al, Ag, and Ti and other metal ions from the doped Si. A further pyrometallurgical smelting at 1520 degrees C using CaO-CaF2-SiO2 slag mixture to scavenge the residual metals after acid leaching could finally produce > 99.998%-grade Si. A process based on HNO3/NaOH leaching and subsequent smelting is proposed for recycling Si from rejected or recycled photovoltaic modules. Implications: The photovoltaic industry is considering options of recycling PV modules to recover metals such as Si, Ag, Cu, Al, and others used in the manufacturing of the PV cells. This is to retain its "green" image and to comply with current legislations in several countries. An evaluation of potential resources made available from PV wastes and the technologies used for processing these materials is therefore of significant importance to the industry. Of interest are the costs of processing and the potential revenues gained from recycling, which should determine the viability of economic recycling of PV modules in the future.

  12. Used float shoe recovered and tested

    SciTech Connect

    Colvard, R.L.

    1986-02-01

    A cement float valve has been recovered after it was circulated through and cemented downhole. It was retrieved by coring as part of an investigation into a cementing failure. The float equipment was then analyzed for downhole performance. This is believed to be the first instance of intact recovery of full-scale cementing hardware after it has been cemented in place. In this instance, the valve performed as designed. Flash set proved to be the probable cause of job failure. This article documents the job and includes photographs of the used float shoe and its components.

  13. The economic value of remote sensing of earth resources from space: An ERTS overview and the value of continuity of service. Volume 4: Forestry, wildlife and rangeland

    NASA Technical Reports Server (NTRS)

    Andrews, J.; Stevenson, P.

    1974-01-01

    The economic value of ERS information in the resource management area of extensive use of living resources, forestry, wildlife, and rangeland, is determined. Timber and forage resources are quantitatively evaluated. It is shown that these resources have economic value in the tens of billions of dollars, but the economic benefits of improved management of the forests and rangelands are not limited to efficiency in the production of these commercial resources. Multiple-use values including watershed, wildlife, and recreation are also involved.

  14. Floral visitation by the Argentine ant reduces pollinator visitation and seed set in the coast barrel cactus, Ferocactus viridescens.

    PubMed

    LeVan, Katherine E; Hung, Keng-Lou James; McCann, Kyle R; Ludka, John T; Holway, David A

    2014-01-01

    Mounting evidence indicates that trade-offs between plant defense and reproduction arise not only from resource allocation but also from interactions among mutualists. Indirect costs of plant defense by ants, for example, can outweigh benefits if ants deter pollinators. Plants can dissuade ants from occupying flowers, but such arrangements may break down when novel ant partners infiltrate mutualisms. Here, we examine how floral visitation by ants affects pollination services when the invasive Argentine ant (Linepithema humile) replaces a native ant species in a food-for-protection mutualism with the coast barrel cactus (Ferocactus viridescens), which, like certain other barrel cacti, produces extrafloral nectar. We compared the effects of floral visitation by the Argentine ant with those of the most prevalent native ant species (Crematogaster californica). Compared to C. californica, the Argentine ant was present in higher numbers in flowers. Cactus bees (Diadasia spp.), the key pollinators in this system, spent less time in flowers when cacti were occupied by the Argentine ant compared to when cacti were occupied by C. californica. Presumably as a consequence of decreased duration of floral visits by Diadasia, cacti occupied by L. humile set fewer seeds per fruit and produced fewer seeds overall compared to cacti occupied by C. californica. These data illustrate the importance of mutualist identity in cases where plants balance multiple mutualisms. Moreover, as habitats become increasingly infiltrated by introduced species, the loss of native mutualists and their replacement by non-native species may alter the shape of trade-offs between plant defense and reproduction.

  15. Workers select mates for queens: a possible mechanism of gene flow restriction between supercolonies of the invasive Argentine ant

    NASA Astrophysics Data System (ADS)

    Sunamura, Eiriki; Hoshizaki, Sugihiko; Sakamoto, Hironori; Fujii, Takeshi; Nishisue, Koji; Suzuki, Shun; Terayama, Mamoru; Ishikawa, Yukio; Tatsuki, Sadahiro

    2011-05-01

    Some invasive ants form large networks of mutually non-aggressive nests, i.e., supercolonies. The Argentine ant Linepithema humile forms much larger supercolonies in introduced ranges than in its native range. In both cases, it has been shown that little gene flow occurs between supercolonies of this species, though the mechanism of gene flow restriction is unknown. In this species, queens do not undertake nuptial flight, and males have to travel to foreign nests and cope with workers before gaining access to alien queens. In this study, we hypothesized that male Argentine ants receive interference from workers of alien supercolonies. To test this hypothesis, we conducted behavioral and chemical experiments using ants from two supercolonies in Japan. Workers attacked males from alien supercolonies but not those from their own supercolonies. The level of aggression against alien males was similar to that against alien workers. The frequency of severe aggression against alien males increased as the number of recipient workers increased. Cuticular hydrocarbon profiles, which serve as cues for nestmate recognition, of workers and males from the same supercolony were very similar. Workers are likely to distinguish alien males from males of their own supercolony using the profiles. It is predicted that males are subject to considerable aggression from workers when they intrude into the nests of alien supercolonies. This may be a mechanism underlying the restricted gene flow between supercolonies of Argentine ants. The Argentine ant may possess a distinctive reproductive system, where workers participate in selecting mates for their queens. We argue that the aggression of workers against alien males is a novel form of reproductive interference.

  16. PROCESS OF RECOVERING URANIUM FROM ITS ORES

    DOEpatents

    Galvanek, P. Jr.

    1959-02-24

    A process is presented for recovering uranium from its ores. The crushed ore is mixed with 5 to 10% of sulfuric acid and added water to about 5 to 30% of the weight of the ore. This pugged material is cured for 2 to 3 hours at 100 to 110 deg C and then cooled. The cooled mass is nitrate-conditioned by mixing with a solution equivalent to 35 pounds of ammunium nitrate and 300 pounds of water per ton of ore. The resulting pulp containing 70% or more solids is treated by upflow percolation with a 5% solution of tributyl phosphate in kerosene at a rate equivalent to a residence time of about one hour to extract the solubilized uranium. The uranium is recovered from the pregnant organic liquid by counter-current washing with water. The organic extractant may be recycled. The uranium is removed from the water solution by treating with ammonia to precipitate ammonium diuranate. The filtrate from the last step may be recycled for the nitrate-conditioning treatment.

  17. Process for recovering organic vapors from air

    DOEpatents

    Baker, Richard W.

    1985-01-01

    A process for recovering and concentrating organic vapor from a feed stream of air having an organic vapor content of no more than 20,000 ppm by volume. A thin semipermeable membrane is provided which has a feed side and a permeate side, a selectivity for organic vapor over air of at least 50, as measured by the ratio of organic vapor permeability to nitrogen permeability, and a permeability of organic vapor of at least 3.times.10.sup.-7 cm.sup.3 (STP) cm/cm.sup.2 sec.cm Hg. The feed stream is passed across the feed side of the thin semipermeable membrane while providing a pressure on the permeate side which is lower than the feed side by creating a partial vacuum on the permeate side so that organic vapor passes preferentially through the membrane to form an organic vapor depleted air stream on the feed side and an organic vapor enriched stream on the permeate side. The organic vapor which has passed through the membrane is compressed and condensed to recover the vapor as a liquid.

  18. When will the Antarctic Ozone Hole Recover?

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph; Montzka, Steve

    2006-01-01

    The Antarctic ozone hole develops each year and culminates by early Spring. Antarctic ozone values have been monitored since 1979 using satellite observations from the .TOMS instrument. The severity of the hole has been assessed from TOMS using the minimum total ozone value from the October monthly mean (depth of the hole) and by calculating the average size during the September-October period. Ozone is mainly destroyed by halogen catalytic cycles, and these losses are modulated by temperature variations in the collar of the polar lower stratospheric vortex. In this presentation, we show the relationships of halogens and temperature to, both the size and depth of the hole. Because atmospheric halogen levels are responding to international agreements that limit or phase out production, the amount of halogens in the stratosphere should decrease over the next few decades. Using projections of halogen levels combined with age-of-air estimates, we find that the ozone hole is recovering at an extremely slow rate and that large ozone holes will regularly recur over the next 2 decades. The ozone hole will begin to show first signs of recovery in about 2023, and the hole will fully recover to pre-1980 levels in approximately 2070. This 2070 recovery is 20 years later than recent projections.

  19. When Will the Antarctic Ozone Hole Recover?

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph; Montzka, Steve

    2005-01-01

    The Antarctic ozone hole develops each year and culminates by early Spring. Antarctic ozone values have been monitored since 1979 using satellite observations from the TOMS instrument. The severity of the hole has been assessed from TOMS using the minimum total ozone value from the October monthly mean (depth of the hole) and by calculating the average size during the September-October period. Ozone is mainly destroyed by halogen catalytic cycles, and these losses are modulated by temperature variations in the collar of the polar lower stratospheric vortex. In this presentation, we show the relationships of halogens and temperature to both the size and depth of the hole. Because atmospheric halogen levels are responding to international agreements that limit or phase out production, the amount of halogens in the stratosphere should decrease over the next few decades. Using projections of halogen levels combined with age-of-air estimates, we find that the ozone hole is recovering at an extremely slow rate and that large ozone holes will regularly recur over the next 2 decades. We will show estimates of both when the ozone hole will begin to show first signs of recovery, and when the hole will fully recover to pre-1980 levels.

  20. Examining differences between recovered and declining endangered species

    USGS Publications Warehouse

    Abbitt, R.J.F.; Michael, Scott J.

    2001-01-01

    Between 1973 and 1999, 43 species in the United States were reclassified from endangered to threatened or removed entirely from the Endangered Species List. Of these, 23 were identified as recovered. In 1999 the U.S. Fish and Wildlife Service (USFWS) published a list of 33 additional species for possible reclassification and/or delisting. We initiated this study to examine why some endangered species recover but others continue to decline and to identify differences in management activities between these two groups. We defined recovered/recovering species as previously recovered species and the additional recovered/recovering species listed by the USFWS. We defined declining species as those identified as declining in the most recent USFWS Report to Congress. Information on recovered/recovering and declining species was gathered from relevant literature, recovery plans, U.S. Federal Register documents, and individuals responsible for the recovery management of each species. We used this information to examine (1) the percentage of current and historic range covered by management activities; (2) threats affecting the species; (3) population sizes at the time of listing; (4) current versus historic range size; and (5) percentage of recovery management objectives completed. Although few statistical analyses provided significant results, those that did suggest the following differences between recovered/recovering and declining species: (1) recovered/recovering species face threats that are easier to address; (2) recovered/recovering species occupy a greater percentage of their historic range; and (3) recovered/recovering species have a greater percentage of their recovery management objectives completed. Those species with threats easier to address and that occupy a greater percentage of their historic range are recovered/recovering. In contrast, declining species face threats more difficult to address and occupy significantly less of their historic range. If this

  1. Plant species richness and shrub cover attenuate drought effects on ecosystem functioning across Patagonian rangelands.

    PubMed

    Gaitán, Juan J; Bran, Donaldo; Oliva, Gabriel; Maestre, Fernando T; Aguiar, Martín R; Jobbágy, Esteban; Buono, Gustavo; Ferrante, Daniela; Nakamatsu, Viviana; Ciari, Georgina; Salomone, Jorge; Massara, Virginia

    2014-10-01

    Drought is an increasingly common phenomenon in drylands as a consequence of climate change. We used 311 sites across a broad range of environmental conditions in Patagonian rangelands to evaluate how drought severity and temperature (abiotic factors) and vegetation structure (biotic factors) modulate the impact of a drought event on the annual integral of normalized difference vegetation index (NDVI-I), our surrogate of ecosystem functioning. We found that NDVI-I decreases were larger with both increasing drought severity and temperature. Plant species richness (SR) and shrub cover (SC) attenuated the effects of drought on NDVI-I. Grass cover did not affect the impacts of drought on NDVI-I. Our results suggest that warming and species loss, two important imprints of global environmental change, could increase the vulnerability of Patagonian ecosystems to drought. Therefore, maintaining SR through appropriate grazing management can attenuate the adverse effects of climate change on ecosystem functioning.

  2. Assessment of Landsat multispectral scanner spectral indexes for monitoring arid rangeland

    NASA Technical Reports Server (NTRS)

    Musick, H. B.

    1984-01-01

    Correlations between spectral indices and vegetation parameters in south-central New Mexico were used to determine the utility of Landsat Multispectral Scanner (MSS) spectral indices in arid rangeland monitoring. In addition, spectral index change for 1976-1980 was calculated from retrospective MSS data and compared with qualitative ground truth in order to evaluate vegetation change detection by means of spectral indices. Brightness index change consistently differentiated between cover increase and decrease, but index change appears to have been offset from true cover change; this may at least partly be attributed to the failure of the methods used to standardize MSS scenes for differences in sensor response. Green vegetation indices, by contrast to brightness indices, failed to consistently differentiate between cover increase and decrease.

  3. Energy biomass from large rangeland shrubs of the intermountain United States

    SciTech Connect

    Van Epps, G.A.; Barker, J.R.; Makell, C.M.

    1982-01-01

    Large individual plants within a few species of rangeland shrubs were studied in several Intermountain States for their potential use in establishing biomass fuel energy plantations. Their locations were based on reports in the literature, suggestions from various range researchers, and personal knowledge. Biomass and other shrub physical characteristics plus site data were recorded for big sagebrush (Artemisia tridentata), fourwing saltbush (Atriplex canescens), big saltbush (A. lentiformis), greasewood (Sarcobatus vermiculatus), rubber rabbitbrush (Chrysothamnus nauseosus), and spreading rabbitbrush (C. linifolius) in 34 locations. Samples of current year's growth and woody tissue were analyzed for burning qualities (heat of combustion, sulfur, moisture, and ash content). Greatest biomass per plant of the individuals sampled was found in greasewood with fourwing saltbush, rubber rabbitbrush, and sagebrush following in decreasing order. Burning qualities varied among the species analyzed. The heat of combustion of the woody material from all shrubs was approximately 4500 Kcal/kg, but current year's growth varied considerably among species. (Refs. 15).

  4. Plant species richness and shrub cover attenuate drought effects on ecosystem functioning across Patagonian rangelands

    PubMed Central

    Gaitán, Juan J.; Bran, Donaldo; Oliva, Gabriel; Maestre, Fernando T.; Aguiar, Martín R.; Jobbágy, Esteban; Buono, Gustavo; Ferrante, Daniela; Nakamatsu, Viviana; Ciari, Georgina; Salomone, Jorge; Massara, Virginia

    2014-01-01

    Drought is an increasingly common phenomenon in drylands as a consequence of climate change. We used 311 sites across a broad range of environmental conditions in Patagonian rangelands to evaluate how drought severity and temperature (abiotic factors) and vegetation structure (biotic factors) modulate the impact of a drought event on the annual integral of normalized difference vegetation index (NDVI-I), our surrogate of ecosystem functioning. We found that NDVI-I decreases were larger with both increasing drought severity and temperature. Plant species richness (SR) and shrub cover (SC) attenuated the effects of drought on NDVI-I. Grass cover did not affect the impacts of drought on NDVI-I. Our results suggest that warming and species loss, two important imprints of global environmental change, could increase the vulnerability of Patagonian ecosystems to drought. Therefore, maintaining SR through appropriate grazing management can attenuate the adverse effects of climate change on ecosystem functioning. PMID:25339654

  5. Factors controlling gully erosion at different spatial and temporal scales in rangelands of SW Spain

    NASA Astrophysics Data System (ADS)

    Gómez Gutiérrez, Á.; Schnabel, S.; Lavado Contador, J. F.; Pulido Fernández, M.

    2009-04-01

    Gully erosion has been recognized as an important soil degradation process in rangelands of SW Spain. However, little is known about gullying processes at different spatial and temporal scales in these areas. Three different approaches were used in this paper to analyze the factors determining gully erosion intensity and rates at different spatial and temporal scales in rangelands of SW Spain. The first approach was based on the monitoring of a permanent valley bottom gully and continuous measurement of rainfall and discharge during the period 2001-2007 in the Parapuños experimental basin. Parapuños is a small catchment (99.5 ha) representative of dehesa land use, with an undulated topography and Mediterranean climate. Gully erosion volume was obtained by means of 28 fixed cross sections measured with a frequency of 6 months. Discharge and rainfall were monitored using a water depth probe installed in a weir at the outlet of the catchment and 6 tipping bucket rain gauges, respectively. The second approach was based on analyzing the development of the same permanent gully located in Parapuños using six series of aerial ortophotographs for the period 1945-2006. This methodology allowed to relate gully evolution with land use and vegetation cover changes. Finally, a relatively new data mining technique, called Multivariate Adaptive Regression Splines (MARS), was applied to construct a model capable of predicting the location of gullies at the regional scale. A large database composed of 36 independent variables related to topography, lithology, soils, rainfall, land use and vegetation cover was used. This statistical technique allowed to determine the importance of the variables involved. This database was gathered in 46 farms representative of rangelands of SW Spain in Extremadura, covering a surface area of 35,459 ha. Farms were quite diverse although their main characteristics were undulating landforms, acid rocks (schists, greywackes and granites), and

  6. Patterns of spread in biological invasions dominated by long-distance jump dispersal: Insights from Argentine ants

    PubMed Central

    Suarez, Andrew V.; Holway, David A.; Case, Ted J.

    2001-01-01

    Invading organisms may spread through local movements (giving rise to a diffusion-like process) and by long-distance jumps, which are often human-mediated. The local spread of invading organisms has been fit with varying success to models that couple local population growth with diffusive spread, but to date no quantitative estimates exist for the relative importance of local dispersal relative to human-mediated long-distance jumps. Using a combination of literature review, museum records, and personal surveys, we reconstruct the invasion history of the Argentine ant (Linepithema humile), a widespread invasive species, at three spatial scales. Although the inherent dispersal abilities of Argentine ants are limited, in the last century, human-mediated dispersal has resulted in the establishment of this species on six continents and on many oceanic islands. Human-mediated jump dispersal has also been the primary mode of spread at a continental scale within the United States. The spread of the Argentine ant involves two discrete modes. Maximum distances spread by colonies undergoing budding reproduction averaged 150 m/year, whereas annual jump-dispersal distances averaged three orders of magnitude higher. Invasions that involve multiple dispersal processes, such as those documented here, are undoubtedly common. Detailed data on invasion dynamics are necessary to improve the predictive power of future modeling efforts. PMID:11158600

  7. Diet-related modification of cuticular hydrocarbon profiles of the Argentine ant, Linepithema humile, diminishes intercolony aggression.

    PubMed

    Buczkowski, Grzegorz; Kumar, Ranjit; Suib, Steven L; Silverman, Jules

    2005-04-01

    Territorial boundaries between conspecific social insect colonies are maintained through a highly developed nestmate recognition system modulated by heritable and, in some instances, nonheritable cues. Argentine ants, Linepithema humile, use both genetic and environmentally derived cues to discriminate nestmates from nonnestmates. We explored the possibility that intraspecific aggression in the Argentine ant might diminish when colonies shared a common diet. After segregating recently field-collected colony pairs into high or moderate aggression categories, we examined the effect of one of three diets: two hydrocarbon-rich insect prey, Blattella germanica and Supella longipalpa, and an artificial (insect-free) diet, on the magnitude of aggression loss. Aggression diminished between colony pairs that were initially moderately aggressive. However, initially highly aggressive colony pairs maintained high levels of injurious aggression throughout the study, independent of diet type. Each diet altered the cuticular hydrocarbon profile by contributing unique, diet-specific cues. We suggest that acquisition of common exogenous nestmate recognition cues from shared food sources may diminish aggression and promote fusion in neighboring colonies of the Argentine ant.

  8. Unmanned Aircraft Systems Used over Western U.S. Rangelands to Characterize Terrestrial Ecosystems

    NASA Astrophysics Data System (ADS)

    Rango, A.

    2015-12-01

    New remote sensing methods to quantify terrestrial ecosystems have developed rapidly over the past 10 years. New platforms with improved aeronautical capabilities have become known as Unmanned Aircraft Systems (UAS). In addition to the new aircraft, sensors are becoming smaller and some can fit into limited payload bays. The miniaturization process is well underway, but much remains to be done. Rather than using a wide variety of sensors, a limited number of instruments is recommended. At the moment we fly 2-3 instruments (digital SLR camera, 6-band multispectral camera, and single video camera). Our flights are primarily over low population density western U.S. rangeland with objectives to assess rangeland health, active erosion, vegetation change, phenology, livestock movement, and vegetation type consumed by grazing animals. All of our UAS flights are made using a serpentine flight path with overlapping images at an altitude of 700 ft (215 m). This altitude allows hyperspatial imagery with a resolution of 5-15 cm depending upon the sensor being used, and it allows determination of vegetation type based on the plant structure and vegetation geometries, or by multispectral analysis. In addition to advances in aircraft and sensor technology, image processing software has become more sophisticated. Future development is necessary, and we can expect improvement in sensors, aircraft, data collection, and application to terrestrial ecosystems. Of 17 ARS research laboratories across the country four laboratories are interested in future UAS applications and another 13 already have at least one UAS. In 2015 the Federal Aviation Administration proposed a framework of recommendations that would allow routine use of certain small UAS (those weighing less than 55 lb (25 kg)). Although these new regulations will provide increased flexibility in how flights are made, other operations will still require the use of a Certificate of Authorization.

  9. Mapping and monitoring cheatgrass dieoff in rangelands of the Northern Great Basin, USA

    USGS Publications Warehouse

    Boyte, Stephen P.; Wylie, Bruce K.; Major, Donald J.

    2015-01-01

    Understanding cheatgrass (Bromus tectorum) dynamics in the Northern Great Basin rangelands, USA, is necessary to effectively manage the region’s lands. This study’s goal was to map and monitor cheatgrass performance to identify where and when cheatgrass dieoff occurred in the Northern Great Basin and to discover how this phenomenon was affected by climatic, topographic, and edaphic variables. We also examined how fire affected cheatgrass performance. Land managers and scientists are concerned by cheatgrass dieoff because it can increase land degradation, and its causes and effects are not fully known. To better understand the scope of cheatgrass dieoff, we developed multiple ecological models that integrated remote sensing data with geophysical and biophysical data. The models’ R2 ranged from 0.71 to 0.88, and their root mean squared errors (RMSEs) ranged from 3.07 to 6.95. Validation of dieoff data showed that 41% of pixels within independently developed dieoff polygons were accurately classified as dieoff, whereas 2% of pixels outside of dieoff polygons were classified as dieoff. Site potential, a long-term spatial average of cheatgrass cover, dominated the development of the cheatgrass performance model. Fire negatively affected cheatgrass performance 1 year postfire, but by the second year postfire performance exceeded prefire levels. The landscape-scale monitoring study presented in this paper helps increase knowledge about recent rangeland dynamics, including where cheatgrass dieoffs occurred and how cheatgrass responded to fire. This knowledge can help direct further investigation and/or guide land management activities that can capitalize on, or mitigate the effects of, cheatgrass dieoff.

  10. Integrating Science and Land Management for the Conservation Effects Assessment Project (CEAP) in Southwestern Rangelands

    NASA Astrophysics Data System (ADS)

    Goodrich, D. C.; Heilman, P.; Nearing, M.; Speath, K.; Hernandez, M.; Wei, H.; Holifield-Collins, C.; Kautz, M.; Nichols, M.; Barlow, J.; Guertin, P.; Burns, S.; Stone, J. J.; Weltz, M.; Metz, L.; Norfleet, L.; Duriancik, L.; Johnson, M.

    2013-12-01

    Farm Bill legislation enacted by Congress in 2002 directed the U.S. Department of Agriculture to assess of the benefits and efficacy of conservation practices provided by a variety of USDA programs. Benefits include improved agricultural production, reduction of erosion and associated nutrient losses, improved water quality, improved soil resilience, and improved habitat among others. To conduct the assessment, the USDA initiated CEAP or the Conservation Effects Assessment Project in 2003, which included a national assessment complemented by small watershed studies. The national assessment started in eastern and midwestern cultivated croplands and has now progressed to western rangelands. This presentation will discuss the challenges of assessing the effects of rangeland conservation practices in a period of unusually hot and dry climatic conditions in the Cienega Creek Watershed (CCW) located southeast of Tucson, Arizona. As is common in the western U.S., the CCW consists of a patchwork of private and public lands in the west with much of the public lands leased for grazing cattle. The watershed also has high recreational value and provides many ecosystem services, including wildlife habitat qualities and flood protection to Tucson. A combination of monitoring, modeling, and remote sensing was utilized in the assessment. Conservation spending in the watershed ramped up in 1997. However, the 16-year period from 1997-2012 contains almost half of the 23 driest seasons (lowest 20 percentile) from the 117-year observed precipitation record. Initial results indicate that Landsat remotely sensed images can be effectively used to estimate both green and senescent canopy cover. This enabled detection of the impacts of drought and changes in canopy cover from practices such as prescribed fire and mechanical brush removal. Cienega Creek Watershed - Land Ownership

  11. Phenological changes in the concentration of alkaloids of Carex brevicollis in an Alpine rangeland.

    PubMed

    Busqué, Juan; Pedrosa, Mercedes Martin; Cabellos, Blanca; Muzquiz, Mercedes

    2010-11-01

    Carex brevicollis (Cyperaceae) is a plant of mesic grasslands in calcareous mountains of southern Europe. It contains two different β-carboline alkaloids, brevicolline and brevicarine, the first of which is thought to produce abortions in mammals. In the rangeland of Aliva, within the Picos de Europa massif in northern Spain, the abundance of Carex brevicollis has been linked with the occurrence of teratogenesis in early gestating cows grazing in early summer. The concentration of alkaloids was measured in the summers of 2007 and 2008, at intervals of 2 weeks, at different altitudes within the rangeland (1,350, 1,600, and 1,850 m) and from different parts of the sedge (leaves, reproductive stems, and inflorescences). Estimated growing degree days were related to the flowering phenology of Carex brevicollis and were used to analyse its relation with the concentration of alkaloids. Brevicarine concentration was higher in inflorescences and brevicolline in leaves. Although it also depended on the zone and year, the concentrations of both alkaloids were related one to another in leaves and inflorescences but not in stems. Both alkaloids decreased with growing degree days in the inflorescences and showed no response in leaves. Our findings suggest that brevicarine, not brevicolline, could be the teratogen in pregnant cattle in this region. This hypothesis is supported by the observed frequent consumption of inflorescences and scarce consumption of leaves of Carex brevicollis by grazing livestock, and also by the coincidence of the toxicity in early pregnant cows with the flowering time of the sedge.

  12. Mapping Erosion Risk in California's Rangelands Using the Universal Soil Loss Equation (USLE)

    NASA Astrophysics Data System (ADS)

    Salls, W. B.; O'Geen, T. T.

    2015-12-01

    Soil loss constitutes a multi-faceted problem for agriculture: in addition to reducing soil fertility and crop yield, it compromises downstream water quality. Sediment itself is a major issue for aquatic ecosystems, but also serves as a vector for transporting nutrients, pesticides, and pathogens. Rangelands are thought to be a contributor to water quality degradation in California, particularly in the northern Coast Range. Though total maximum daily loads (TMDLs) have been imposed in some watersheds, and countless rangeland water quality outreach activities have been conducted, the connection between grazing intensity recommendations and changes in water quality is poorly understood at the state level. This disconnect gives rise to poorly informed regulations and discourages adoption of best management practices by ranchers. By applying the Universal Soil Loss Equation (USLE) at a statewide scale, we highlighted areas most prone to erosion. We also investigated how two different grazing intensity scenarios affect modeled soil loss. Geospatial data layers representing the USLE parameters—rainfall erosivity, soil erodibility, slope length and steepness, and cover—were overlaid to model annual soil loss. Monitored suspended sediment data from a small North Coast watershed with grazing as the predominant land use was used to validate the model. Modeled soil loss values were nearly one order of magnitude higher than monitored values; average soil loss feeding the downstream-most site was modeled at 0.329 t ha-1 yr-1, whereas storm-derived sediment passing the site over two years was calculated to be 0.037 t ha-1 yr-1. This discrepancy may stem from the fact that the USLE models detached sediment, whereas stream monitoring reflects sediment detached and subsequently transported to the waterway. Preliminary findings from the statewide map support the concern that the North Coast is particularly at risk given its combination of intense rain, erodible soils, and

  13. Atypical morphology of dark septate fungal root endophytes of Bouteloua in arid southwestern USA rangelands.

    PubMed

    Barrow, J R

    2003-10-01

    Native grasses of semi-arid rangelands of the southwestern USA are more extensively colonized by dark septate endophytes (DSE) than by traditional mycorrhizal fungi. Roots of dominant grasses ( Bouteloua sp.) native to arid southwestern USA rangelands were prepared and stained using stains specific for fungi (trypan blue) and for lipids (sudan IV). This revealed extensive internal colonization of physiologically active roots by atypical fungal structures that appear to function as protoplasts, without a distinguishable wall or with very thin hyaline walls that escape detection by methods staining specifically for fungal chitin. These structures were presumed to be active fungal stages that progressed to form stained or melanized septate hyphae and microsclerotia characteristic of DSE fungi within dormant roots. The most conspicuous characteristic of these fungi were the unique associations that formed within sieve elements and the accumulation of massive quantities of lipids. This interface suggests a biologically significant location for carbon transfer between the plant and fungus. The continuous intimate association with all sieve elements, cortical and epidermal cells as well as external extension on the root surface and into the soil indicates that they are systemic and considerably more prevalent than previously thought. A fungal network associated with a mucilaginous complex observed on the root surface and its potential role in root function in dry soil is discussed. It is suggested that those fungi that non-pathogenically and totally colonize plant cells be classed as systemic endophytic fungi (SEF). This would refine the broad designation of DSE fungi. The potential mutualistic benefit of SEF for native plants in arid ecosystems based on the extent of lipid accumulation and its apparent distribution is discussed.

  14. Evaluation of hydrologic parameters in a semiarid rangeland using remotely sensed spectral data

    NASA Astrophysics Data System (ADS)

    Moran, M. S.; Clarke, T. R.; Kustas, W. P.; Weltz, M.; Amer, S. A.

    1994-05-01

    A study was conducted to determine the relation between remotely sensed spectral data and measurements of vegetation-related hydrologic parameters in a semiarid rangeland in southeast Arizona. Throughout the measurement periods, ranging from June to September 1990, eight sites in the U.S. Department of Agriculture's Agricultural Research Service Walnut Gulch experimental watershed were monitored for water and energy fluxes and other meteorological and biological parameters. Corresponding spectral data were acquired with ground-based radiometers, low-altitude aircraft-mounted instruments, and Landsat thematic mapper sensors. Spectral indices were derived from measurements of surface reflectance, based on their response to variations in hydrologic parameters and sensitivity to unrelated variables, such as solar zenith angle and soil differences. A soil-adjusted vegetation index, SAVI (derived from red and NIR reflectance factors), was found to be highly correlated with the temporal changes in vegetation cover and biomass, but less successful in discriminating spatial differences in cover and biomass across the watershed. Significant relations were found between the surface-air temperature (Ts-Ta) difference and measurements of soil moisture content, though the shape differed from that previously published for bare soil. The relation between daily evaporation rate and measurements of (Ts-Ta) and daily net radiation was similar to that derived previously for irrigated pasture and dryland shortgrass in France but differed from that derived for irrigated wheat. These results emphasized the strengths and limitations of the use of spectral data for estimation of hydrologic characteristics of sparsely vegetated sites and suggested a need for reevaluation of common empirical relations between remotely sensed measurements and surface characteristics for application to rangeland areas.

  15. Palaeoceanographic significance of sedimentary features at the Argentine continental margin revealed by multichannel seismic reflection data

    NASA Astrophysics Data System (ADS)

    Gruetzner, Jens; Uenzelmann-Neben, Gabriele; Franke, Dieter

    2010-05-01

    The thermohaline circulation in the Argentine Basin today is characterized by the interaction of northward flowing Antarctic water masses (Antarctic Intermediate Water, AAIW; Circumpolar Deep Water, CDW; Antarctic Bottom Water, AABW) and southward flowing North Atlantic Deep Water (NADW). The transfer of heat and energy via both AABW and NADW constitutes an important component in maintaining the global conveyor belt. We aim at a better understanding of both paths and intensity of this current system in the past by investigating an extensive (> 11000 km) set of high quality seismic reflection profiles from the Argentine continental margin. The profiles show a significant contourite system containing both erosive and depositional features that formed through the evolution of water masses and their modifications (path, physical and chemical properties) due to plate tectonic events such as the opening of the Drake Passage or the extensive emplacement of volcanic flows at the Rio Grande Rise. Overall the depositional features indicate that along slope (contour current) transport dominates over down slope (turbiditic) processes at the southern Argentine margin south of 45° S. Further to the North down slope transport was more extensive as indicated by the presence of submarine canyons crossing the slope down to a depth of ~3500 m. Here we present preliminary results from the southern part of the continental margin (42°-50° S) where we focus on a set of ~50 km wide terraces on the slope and rise separated by contouritic channels. The terraces developed over time in alternating constructional (depositional) and erosive phases. An initial age frame was developed by mapping regional reflectors and seismic units known from previous studies. The sedimentary layer between regional reflectors AR 4 and AR 5 spanning roughly the time interval from the Eocene/Oligocene boundary to the early middle Miocene is thin (0.1 - 0.4 s TWT) below the Valentine Feilberg Terrace but

  16. PROCESSES OF RECOVERING URANIUM FROM A CALUTRON

    DOEpatents

    Baird, D.O.; Zumwalt, L.R.

    1958-07-15

    An improved process is described for recovering the residue of a uranium compound which has been subjected to treatment in a calutron, from the parts of the calutron disposed in the source region upon which the residue is deposited. The process may be utilized when the uranium compound adheres to a surface containing metals of the group consisting of copper, iron, chromium, and nickel. The steps comprise washing the surface with an aqueous acidic oxidizing solvent for the uranium whereby there is obtained an acidic aqueous Solution containing uranium as uranyl ions and metals of said group as impurities, treating the acidic solution with sodium acetate in the presenee of added sodium nitrate to precipitate the uranium as sodium uranyl acetate away from the impurities in the solution, and separating the sodium uranyl acetate from the solution.

  17. BACKUP -- Recovering from incremental tape backups

    NASA Astrophysics Data System (ADS)

    Allan, P. M.

    The importance of making regular backups of your disks in well known, but it can be very frustrating to have a head crash and then discover that you cannot recover from your backups because the manuals do not tell you what to do. The DEC documentation covers most possibilities, but not the case where a removable pack is copied to a new pack, the new pack is then used as the current pack, and incremental backups to tape are then made. This situation is a fairly common one when you have two or more removable disk drives. This note covers backup and recovery in general terms, and details exactly what to do in the above mentioned case.

  18. Apparatus to recover tritium from tritiated molecules

    DOEpatents

    Swansiger, William A.

    1988-01-01

    An apparatus for recovering tritium from tritiated compounds is provided, including a preheater for heating tritiated water and other co-injected tritiated compounds to temperatures of about 600.degree. C. and a reactor charged with a mixture of uranium and uranium dioxide for receiving the preheated mixture. The reactor vessel is preferably stainless steel of sufficient mass so as to function as a heat sink preventing the reactor side walls from approaching high temperatures. A disposable copper liner extends between the reaction chamber and stainless steel outer vessel to prevent alloying of the uranium with the outer vessel. The uranium dioxide functions as an insulating material and heat sink preventing the reactor side walls from attaining reaction temperatures to thereby minimize tritium permeation rates. The uranium dioxide also functions as a diluent to allow for volumetric expansion of the uranium as it is converted to uranium dioxide.

  19. Recovering Velocity Distributions Via Penalized Likelihood

    NASA Astrophysics Data System (ADS)

    Merritt, David

    1997-07-01

    Line-of-sight velocity distributions are crucial for unravelling the dynamics of hot stellar systems. We present a new formalism based on penalized likelihood for deriving such distributions from kinematical data, and evaluate the performance of two algorithms that extract N(V) from absorption-line spectra and from sets of individual velocities. Both algorithms are superior to existing ones in that the solutions are nearly unbiased even when the data are so poor that a great deal of smoothing is required. In addition, the discrete-velocity algorithm is able to remove a known distribution of measurement errors from the estimate of N(V). The formalism is used to recover the velocity distribution of stars in five fields near the center of the globular cluster omega Centauri.

  20. Characterization of Argentine honeys on the basis of their mineral content and some typical quality parameters

    PubMed Central

    2014-01-01

    Background The levels of 19 elements (As, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Se, Tl, U, V, Zn) from sixteen different Argentine production sites of unifloral [eucalyptus (Eucaliptus rostrata), chilca (Baccharis salicifolia), Algarrobo (Prosopis sp.), mistol (Ziziphus mistol) and citric] and multifloral honeys were measured with the aim to test the quality of the selected samples. Typical quality parameters of honeys were also determined (pH, sugar content, moisture). Mineral elements were determined by using inductively coupled plasma mass spectrometer (ICP-MS DRC). We also evaluated the suitability of honey as a possible biomonitor of environmental pollution. Thus, the sites were classified through cluster analysis (CA) and then pattern recognition methods such as Principal Component Analysis (PCA) and discriminant analysis (DA) were applied. Results Mean values for quality parameters were: pH, 4.12 and 3.81; sugar 82.1 and 82.0 °brix; moisture, 16.90 and 17.00% for unifloral and multifloral honeys respectively. The water content showed good maturity. Likewise, the other parameters confirmed the good quality of the honeys analysed. Potassium was quantitatively the most abundant metal, accounting for 92,5% of the total metal contents with an average concentration of 832.0 and 816.2 μg g-1 for unifloral and multifloral honeys respectively. Sodium was the second most abundant major metal in honeys with a mean value of 32.16 and 33.19 μg g-1 for unifloral and multifloral honeys respectively. Mg, Ca, Fe, Mn, Zn and Cu were present at low-intermediate concentrations. For the other 11 trace elements determined in this study (As, Be, Cd, Co, Cr, Ni, Pb, Se, Tl, U and V), the mean concentrations were very low or below of the LODs. The sites were classified through CA by using elements’ and physicochemical parameters data, then DA on the PCA factors was applied. Dendrograms identified three main groups. PCA explained 52.03% of the total variability